I think the reaction on the site itself also suffered from the AMA getting hard buried.
Which was stupid. People should have upvoted the post in the AMA sub which was just a link to the AMA on the Reddit sub. It wasn't even pinned. And even if you did find it, until they did a summary you couldn't see his responses because also buried (understandably)
That said, yes, I agree with you and the adjacent poster - the upside is alternative platforms got a huge boost, and even if a lot of the influx doesn't stay, it's still a huge boost.
I don't think Reddit will immediately reverse course, but I think the protest has been an absolute win simply by giving the alternative communities far more growth than they would have otherwise.
Reddit needs competition to feel threatened.