Then the botnet will just be honest for like a year before it abuses the network. Even better because now honest new clients can be kicked as they disagree with the bot majority. So now the network bleeds users.
Checking which account is honest isn't too hard, you detect that there is a "problematic mismatch" between two clients. So the project runs their own client to check. If one has an exact match, then you'd question the other.
There is a challenge for sites that serve different content based on GeoIP, A/B testing, dynamic content, etc. So some human review of the diff may help check for malice. If there's literally spam, human review would clearly detect this and that bot is distrusted.
Then I'll simply use more bots to get 80% of the network, then I can almost always win any disagreements and your "problematic mismatch" never triggers.
Plus I can now cause you to have to run your own crawler anyway and either slow progress or cost you a lot of money.
