[scholia]

We have computers that block spam, remove content from Google's index, drive cars and win at Jeopardy. They could certainly remove a lot of abuse, and that would be worth doing.

I'm not convinced it would result in wrongly removing a lot of people, since there is some form of karma in the number of followers and the number of lists someone is on.

Of course, it would be nice to have some recourse to an independent appeal if something goes wrong. However, Google manages without one (1), and its decisions can have devastating personal and financial consequences. That's not the case with Twitter, where there is no real barrier to creating accounts. Including spam accounts.

(1) Unless you happen to be buddies with someone at Google.