How is what I said not clear? While I don't think he's a great or even a good writer (I can cite the bad writing everywhere in BG2), he is leagues ahead of those credited as lead writers on Siege.
He's leagues ahead in terms of what, weight? He was the one that made Hawke gender altering the sexual preference of everyone in the party and even Dragon Age books are filled with subtle but tedious references from todays politics, he's a social parasite obsessed with inclusiveness.
Pretty sure that Gaider's on record as not being a fan of making all romanceable companions bisexual, there were definitely posts of his on the now-purged BSN at the time saying something to the effect of it wasn't his preference/choice to go with that approach. Try to remember that this was the peak of degeneracy on the BSN, with a veritable ocean of rainbow banners and determined picketing of any suggestion that future companions have a set orientation. Given that last I checked, Laidlaw had taken to listing his pronouns and "poly" status on his twitter profile, he'd be the safer bet in my eyes as the guy who mandated that approach, given the number of other "innovations" he gifted the franchise with from DA2 onwards. Can't comment on the books myself as I never read them but I really don't think Gaider has sunk to the level of "slash-fanfiction everyone's bi just because" just yet.
That being said, there's little denying that BioWare was the patient zero of the recent sjw outbreak in gaming, I remember a post by Gaider himself, shortly after DA2 released,giving a dressing down to an "entitled" gamer complaining that the romances for straight male gamers in DA2 were pretty shit. Curiously a whole bunch of "gaming journalists" simultaneously decided to run articles decrying said poster (and by extension entitled, straight male gamers). I found it strange that so many outlets would launch into a mini-assault against their primary audience but boy did it make it easy to discern what was going down when GG rolled around several years later.
It remains to be seen exactly how much of BioWare's decline can be attributed to Gaider, and indeed this theoretical IE-esque game under Beamdog would have demonstrated definitively if he was now in it for the politics or the games, but now we'll probably never know. At the very least, Gaider hasn't done himself any favours running his mouth off, it's been all downhill since DA:O so he really only has his pre-2009 laurels to rest on.