> Within a few months after welcoming the bridge, we were routinely dealing with a sizable and often automated abuse load from the bridge that made use of easy anonymous registration and the protocol’s persistent and distributed archiving of files, including images, videos, and long messages converted to pastebins.

Umm libera itself allows "easy anonymous registration". You don't even need to have an account. You just join with a made-up name if you want to.

This is in fact one of the things I love about IRC. Nothing wrong with it but it feels wrong calling matrix out on that.

The archiving makes kinda sense for matrix' features of scrollback on demand. I believe there's an IRCv3 feature for it too. The bridge should have a provision to prevent users to see any backlog from before the moment they joined.

Ps I really hate those new "single puppet" third party bridges they recommend. Because they break nick colouring and also the actual nick of the user speaking is in a different place. Having each matrix user have their own IRC puppet is much nicer on the IRC side. Especially when there's more matrix than irc users.