The following was a temporary solution that was used until lagbots were fixed.

RACIST bots are a collection of tf2 bot accounts that join casual games en masse and spinbot.

What makes these bots different, however, is how commonplace they are and their tendency to launch a denial of service attack against their current server when a votekick is initiated against them.

There isn't much you can do to stop them from terrorizing others' casual matches, besides spreading this guide, and reporting their profiles, but you can prevent them from ruining YOUR games.

The answer is surprisingly simple
1. Open the steam overlay in game
2. Click the View Players button
3. Find and view the profile of the bot (usually RACIST _____)
4. Press the "more" button and click "Block all communication"

Doing this will prevent valve matchmaking servers from putting you and this specific bot in the same game. If you manage to do this to enough of them (as they usually join in groups), you should be able to enjoy TF2 again!

Thanks for reading!