I’ll dig it up for you shortly, to summarise he talked about dual spec and also other specialization mechanics (such as in Diablo) and talked about the loss of meaningful choice mong other things. I saw that as an unintended impact.
To be fair, some have overstated it as “regret”. I don’t read it that way. More that he realised there were good and bad things with the feature - trade-offs.
I’ll find the quote and put it in this comment for reference. There’s a few different quotes on the topic.
And where I found snips before: