Pssh, any way I see it, if the ending makes sense to you, then you've played it with all DLC on your first go, and if it made sense to you in march 2012, there's headcanon going on.
ME3 has several dropped or confused subplots along the way so there's no reason to suddenly believe the ending is any more thought through, when fans including myself had literally been scouring the codex entries, websites and discussions through to find out what the hell just happened and come out with the conclusion that "I'm reading more into this than those who wrote it did".
I firmly believe the endings don't make sense, and I stand by that. It contradicts ME1 at large even with Leviathan and given how many other things that ME3 got wrong, the game already had done so little to convince me that I knew when I saw the ending that it was just bullshit.
You are of course entitled to your opinion and if you believe the ending is great, more power to you, and with all that said, the ending can be explained via retroactive addition, like Leviathan and Extended Cut. I personally think EC worked in the game's favor (while Leviathan seems way too convenient and cheap as someone who got slapped in the face with the unfinished mess from march 2012). NB: It can be explained, but that's not to say it suddenly makes it good.
I don't say I know the lore better than the writing staff. I can't know that, but as a reader you take what you're given and if **** doesn't add up and has a large consensus that it doesn't, it's the writers' fault. Look at Far Cry 3 for instance, where people started giving it **** because its plot was a jumbled mess and then the writer came out trying to explain what his intention was and the problem there was too, that, whatever he tried to do with his writing, it just didn't come across properly... the execution wasn't well done. Same story here, only, because of Extended Cut, the leaked script and several odd subplots that didn't feel properly fleshed out, I'm inclined to believe the writers' just didn't have the answers lying around in detailed scribbles on their office desk... they simply didn't have it until fans raged and they tried to come up with answers after the fact. NB: It can be explained but it doesn't make it good.
*snip*
And I'm sorry that some of us try to make sense of the ending and you dislike it
That's completely fine. But it's rather condescending of you to say those who liked the end didn't pay attention to the rest. ME has flaws in general, but we can still try to find a way to support certain ideas and themes.
Incidentally, have you played the MGS games? You know those moments in MGS4 when you beat one of the bosses and you get a long exposition dump about child-soldiers and their brutal past? Kind of the same problem... yeah, sure, war is a big theme in MGS4, but this feels like it doesn't have enough of a relation to the overall story of the game. I believe there are certain rules of narrative you have to follow as a writer, just as any musician has to follow rules of music to a certain extent, and by ME3's ending they broke too far out of the rules of narrative and the narrative coherence is lost because of it. It doesn't matter if there's a general theme about synthetics somewhere in the trilogy apart from the ending. It still has to be delivered in a coherent fashion, like I said earlier, in "sort of like an argument, where you make a point". Whatever point ME3's ending was trying to make didn't have the As, Bs or Cs of logical reasoning across the rest of the game to justify raising the issue of organics and synthetics being the central conflict at large. If you can't see that, then at the very least, promise me you'll never become a writer yourself.