Not the most fortunate reaction to criticism.
Quite a lot of people from RPGCodex like and supported his other titles, so it´s kinda natural they´re disappointed when it seems Avadon has "shifted alliances".
Jeff also cherry picked the most throwaway comments and left most of the actual criticism (some of which has been voiced here as well) unaddressed.
I think he may be needlessly alienating quite significant chunk of his fan base with the article.
Still, even though I don´t think he went the right way about it, it must have taken some balls to address criticism this relatively directly and an interesting discourse may come out of it.
Don´t think so.
If speaking strictly about AAA titles, the genre may have gotten simplified throughout the years, but that´s old news - when Ultima 7 came out it was often called dumbed down compared to Ultima V and when I´ve played Baldur´s Gate 2 I remember thinking how awfully streamlined the game was compared to, say, Ultima Underworld 2, Realms of Arkania 2 or Wizardry 7.
So yep, as mainstream gains on volume, AAA titles are loosing challenge or complexity or whatever.
However, compared to, say, 2006, I think that situation is overall pretty good for RPGs nowadays.
I don´t think there´s any decline on action-y RPGs front, thanks to the "middle/AA" devs like Piranha Bytes, Larian or CDProjekt. And Obsidian even made a very multifaceted AAA RPG last year.
And with relative success of Knights of the Chalice and Age of Decadence, Dead State or Frayed Knights on the horizon, I think there might be revival of turn based RPGs incoming as well.
The genre does not stand or fall by Bioware and it´s not like Dragon Age 2, or Arcania for that matter, were glaring successes.