Yeah, I can certainly imagine situations where this approach could get messy. Though if a forum admin felt strongly enough about it, and accepted the risks, the options are there.
Personally, I think the defaults are a pretty good flow (and the Account Deletion Request button is a nice addition too).
This makes sense to me too. I think if a site has taken this decision it has generally come from a place where they want the user to have the ability even if it’s painful for the forum as a whole. If the user decides to push the button then it’s something they have to accept/tolerate, whereas it may not be something they want to encourage as a staff policy.