It can be that hard to make, but it's not as hard as BioWare makes it sound. I've been watching the modders. They've just got some minor tweaks left to do. They just can't create custom meshes like they could in say, Origins. They have to work with the existing ones and that can get tricky sometimes. There is a reason I've found only about 1/2 a dozen since launch. Hair is a big deal on the daitools forums as well as the modding thread here on the BSN. Don't doubt that. They are working on it, but this stuff isn't quite as easy as some might think. 
I know modders do this in their free time, and the devs are still pretty busy working on the game. The patch cycle reflects that to me. However, I see no reason why they couldn't just ask for permission from the modders to use their creations and clean it up for the game. For every player to use. I've seen Valve do it, I've seen Bethesda do it.
I've (happily) watched indy games like the Kirball Space Program and reddit community become so much better from the devs and modders working together. The game started in early beta for Early Access, and I've seen it come a long way. They asked permission from the some of the modders to use their stuff for the game, and then they were able to give it to everyone. Guess how many modders said, "No, give me money?" If you guessed zero, you would be correct. The creators that do this aren't looking to get rich.
Also, I'm not saying the DA team should consider every hair or armor mod. Seriously, I saw one that looked like a 1960s prom queen in one of the hair mod packs I downloaded for Origins. Then there is stuff like the magician's costume up there, which is, um, probably not the best for the base game. I'm not knocking on how hard that modder must have worked, so don't get me wrong there.
I know the DA team still plays games, and this game does reflect that.* However, I wish they would work a little more closely with the modding community. I've been lurking, and damned if they aren't some of the most enthusiastic about the game on the entire forums.
*Before someone pops out of lurk mode to come down on me, please remember that I don't hate on anyone if they despise the game. I'm not apologizing for my views though. I haven't in months, and I never will again.
Try not to get too upset about this though. Sure, it sucks, but it is a game at the end of the day. I know they never meant any harm. As one of the devs said awhile back, some folks are interpreting "intent" for "compromise." They never meant to slight us, although I think their compromise was overall a poor one.
I'll be honest here. I have stated and will continue to state that the devs needed to work on bug fixes and DLC first. That should always be their first priorities, no matter how much the beige and sideburns make us cringe. As far as not adding it to TBE, they just wanted to make sure the CC mirror didn't break the game, and it did cause some bugs for a lot of players. So they probably wanted to start with that and go from there.
It would be nice to see something in the next couple of months though, while they are working on the next DLC and continuing the patch cycle (The Cycle Must Continue.) Being patient does me no harm and saves me a world of grief. I'm not trying to get preachy, so I'm sorry if I come across that way. I just don't like seeing buddies of mine on the forums getting overly stressed out about the hair and clothes problem issue. <hugs>
I figure in the meantime, don't get mad, just stay constructive. I have no doubt that the devs hear us, and I don't think they are trying to be dismissive. I would like it if they at least said, "Stop hoping until after the next story DLC," or "We're working on it," or even "We're listening" as a post on the forums. I hope I would not have to pay for the chance to get more hair/clothes options, but I would be willing if it's under, say, $7 or so. I would prefer a tinting table for the clothes, because I think the armor one went over very well.
I know why they picked beige, and it's still a lame excuse. The dirt build up can go away after a few minutes, or with a quick save/reload. If you spend most of your time on the pavement and stone at Skyhold (like I do after it's built up,) and resist the urge to throw yourself off of the battlements for giggles, the dirt isn't visible. It shows up the most if you jump off of somewhere high, or run around in the dirt too much. I think that most players wouldn't give a crap about that considering that it doesn't take a lot of quests to get most of Skyhold paved. Using the quick travel also mitigates much of this issue as well.
Hey, as long as I'm being a super optimist, maybe they could ask permission from the creator of the No Sideburns mod to use in the game. That would be a major first step in the right direction. That would be awesome, but something I can't expect.
I don't know if I'm misinterpreting you, but if you thought I was saying modders were slow that wasn't my intention. I know it's hard without dev tools. I just thought that if Bioware said they can make hair relatively fast, well, that makes me sad. Both because I don't understand why they wouldn't give the Inquisitor much love before launch and because they won't even after launch, with all the complaints. You can see the detail they put into the other characters, the environment and creatures in that article, but it's like they forgot to make the Inquisitor more than a placeholder until the last minute. Honestly, the pajamas really look like a placeholder.
Are the devs busy? No doubt. But I still think they could find time (especially if it's easier than what I feared) between patches and DLC to add just a few options. It would do wonders to please people, and even make some more likely to buy the next DLCs. Having the team take the ideas of the community both in the form of mods and otherwise is awesome. I really wish they would do what you've said other developers have done. It's like someone doing your job for you! What's not to like, even for EA?
I don't understand why they wouldn't. But like you said, I really, really, really just want them to tell us something. That wouldn't be hard, despite what others think. I wish they'd work with the modding community, but honestly, just the community in general. You'll find tons of great ideas here.
While I generally agree that they should prioritize DLC and patches, I still think they should semi-prioritize removing sideburns. It's just... insulting. I know that seems like an extreme reaction, and I'm not even saying they did it to insult anyone, but it is, to me. Just... ugh. That may just be me getting too personal, I don't know. You mentioned a great idea though, of having the devs use the No Sideburns mod, so that would help them make it a reality with less work. As for the other, purely aesthetic stuff, I would hope that they could more or less work on DLC and that at once in the same way they can make appearance packs. Especially in the period where modellers are done a DLC and waiting for direction on a new one. If that's a thing. I don't know 
I hope they didn't release anything with the BE so they didn't break anything (with the intention of adding more later, of course). Believe me, I wish I could be patient (and I wouldn't really call waiting 6 or so months as being impatient), but I can't really choose. I keep hoping, and keep learning it's not a great idea. Hey Bioware, hearing from you would help me be patient!
Thanks though, I appreciate that. I'm trying to be positive. Am I positive? Honestly, knowing me and my habit of getting every DLC for every game I have, I'd probably pay for some too. Unless they're not good either, of course. Haha, could you imagine? Getting a hair pack with terrible hair? 3 more buzzcuts and a few long styles with balding and sideburns! No. No. Let's not... go there. /Templar
Yeah... beige. I don't want to sound spoiled here, but couldn't they have just disabled dirt buildup in Skyhold? Maybe?
It's pretty over-the-top in general. And yeah, I fast travel around Skyhold mostly, so it's barely there. Whew, long reply to longer post done. I hope you feel better!