Given the fact that it's possible to "nuke" a spambot account, ie delete all posts, why isn't this possible for normal users? I've seen other users asking about deleting an account and the only reply is "we don't do that, change your passwd to something random and go drinking".
Posts made by spambots are obviously spams because it is by AI and AI is never perfect or equal to humans. When it is made by normal users(humans), spam posts will be ther but there will be helpful posts too compared to a bot. I think it is hard for a admin/mod to know which is helpful. So such accounts are left untouched.
Just my 2 Satoshis.