Thabeet's gotten plenty of playing time on different teams to show he sucks. Baynes has gotten a little playing time and shown himself to be a serviceable low-ceiling player. I'll take Baynes' dead-end mediocrity over Thabeet's straight-up horrid play.
By the way, it doesn't matter that he played for the Thunder. He's been so insignificant in his career, that I don't even associate him with a team.
You sound like the guys who were trying to convince me that trading Danny Green for Evan Turner last season would be a no-brainer.