First of all, both DAO and DA2 were in the same boat. As a matter of fact, all of Bioware's games up to Mass Effect 3 were in the same boat. There were no gays or lesbians in DAO/DA2 unless you made one. With the exception of a very brief Karl x Anders interaction in DA2 that implied a relationship, or the implication that Danarius was having his way with Fenris.
Furthermore, those only list games I've played.
Great. So this is why DAI was awarded special recognition by GLAAD for its portrayal of LGBT characters.
BioWare has been actively increasing LGBT representation. This is nothing new.
Like it's predecessors, DAI allows the character to play an LGB (and possibly T if you are vigilant enough) character unlike most games out there.
The inquisitor can flirt with most of the team as any gender.
Four of those characters potentially reciprocate homosexual advances. Those characters are three-dimensional have unique stories and personalities.
You have the witty and charming Dorian who has proven to be a player favorite, with a side quest that resonates with many LGBT people, including me.
You have the brazen and immature Sera who quickly dismisses most lesbian stereotypes etc..
Then there are the (optional) sex scenes that unabashedly portray sexuality in a mature way.
Also, BioWare games approach those relationships differently in that they are actively recognized.
In most other games, relationships are either completely tangential (as in Skyrim) or completely player-created (as in Sims).
Not only that, but Dragon Age Inquisition is one of the few games out there that portrays a transgender character in a non-stereotypical and inoffensive way.
Does it seem a little overt? I fail to see how "in-your-face" the whole Krem situation is when it is only mentioned once in a very tongue-in-cheek manner while meeting the Chargers. The player has to steer the conversation towards the transgender topic so it basically allows the player to react to the transgender character with acceptance, nonchalance, or confusion (after which IB and Krem explain it to you).
Furthermore, DAI shows LGBT main plot characters in power in the form of the lesbian empress Celene and her spymistress and jilted lover Briala.
It allows the player to actively reunite them.
In addition to that, there are several instances of LGBT content that are both explicit and implicit.
An example would be a random dialogue in the Winter Palace between two men presumably in a relationship, with one of them jealous of the other for talking to the Grand Duke Cyril de Montfort whom you would know from DA2.
So all in all, I fail to see how other games compete when it comes to LGBT representation in a AAA game.
Mass Effect 3 is pretty close, but the mono-gendered Asari spacebabes aren't exactly the best analogue to human society.