That seems to be more about changing him into Kid Flash (Which I agree was an inexplicable editorial decision and outwith his control), it was the complete failure to DO anything with Bart once he WAS Kid Flash which I had even more of an issue with. Teen Titans became the Kon/Cassie/Tim show, saddling us with Kory and Vic in unnecessary and never convincing mentor roles, and overlooking the two characters he'd done most to; Raven and Bart.
Waid also says "but even as Kid Flash, he was still largely recognizable as Bart", which I have to disagree with.