I get the spirit of this project is to increase safety, but if the above social contract actually becomes prevalent this seems like a net loss. It establishes an exploitable path for supply-chain attacks: attacker "proves" themselves trustworthy on any project by behaving in an entirely helpful and innocuous manner, then leverages that to gain trust in target project (possibly through multiple intermediary projects). If this sort of cross project trust ever becomes automated then any account that was ever trusted anywhere suddenly becomes an attractive target for account takeover attacks. I think a pure distrust list would be a much safer place to start.