yes but isn't that the beauty of the relay nodes? If you just have one more node in your list, then you're fine. And I know you're saying that people won't add those relays, but I wonder if just the fact that they have the option to add more relays will keep everyone more honest. It's like Bitcoin, just the fact that it exists makes it harder to central bankers to print infinitely, because their actions will show up in the price of something. So if a relay bans someone for purely political reasons, it will just harm that relay and drive people to another.

Of course people could simply choose to only add the most popular relays, or be tricked into thinking the more niche relays are 'dangerous', but I'm not sure any protocol can solve that. All we can do surely is just give people the choice, make it easy for non technical users to make that choice, and just hope that people aren't stupid. If they are stupid, then that's just a human problem.