I'm starting to believe that rollups that don't follow Ethereum's ordering rules (and to some extend censorship-resistance) don't really inherit Ethereum's security.

20. hacking @ https://www.spire.dev/ 
previously intern Nethermind, epns.io

It was clearer in my head, but basically, if you have a centralized sequencer that can censor and order tx as they want I don’t consider that it inherits Ethereum’s security. Precisely for the ordering itself PBS + no centralized proposers are enough I guess