How about a service that lets bruteforcers "in" after some number of failed attempts, but what they get is just a fake command prompt that accepts all of their commands? I'm sure hackers would eventually adapt, but it would annoy them for a while.
They would just connect, issue some command like ‘ls’ and evaluate the response, not sure that would slow them down much more than they already are.
I can't tell if that's sarcasm, but that's a thing already, called honey pot. Very often, you set it up to let attackers in so you can analyze what they're doing and protect yourself better.
