Automoderation (REGEX)

If "discord did it" was a good metric, neither of us would be looking at this repository. I'm up for having my mind changed, but I'd need some arguments in that case. For example, how would you stop someone from setting up thousands of regexes (probably across several communities) filled with compute-intensive recursive lookaheads, and then having their botnet spam messages in said communities, allowing them to nuke servers?