I imagine that Brennan Lee Mulligan walks a fine line as a public figure.
He still plays D&D often enough to (seemingly) not alienate people at Wizards whose work helped launch his career.
But he also plays significant amounts of other games, including some that I think are Indie developers, like Kids on Bikes.
I'm sure he's aware of the issues and concerns in the community around D&D under Wizards - and probably shares many of those same concerns, as a fellow player and DM.
But, yes, the idea that Brennan secretly hates anything sounds pretty silly. Brennan has been pretty direct with his epic rants about things he really hates.
How much longer will we need people who understand how things work?