FYI: Matrix has launched https://archive.matrix.org, which makes logs of world-readable Matrix channels indexable by search engines.
They made the thing opt-out; the bot (@archive:matrix.org) automatically joins out of nowhere and start archiving. You'd have to ban the bot for it to be removed, which is annoying but OK... if they didn't have a second bot ban evade and do the exact same thing right afterwards under https://staging.archive.matrix.org/ using @archive:gitter.im yesterday.
@n0toose Mhh, shouldn't something like this be more opt-in than opt-out?
@n0toose *extremely frizzly fluffed-up cat glare at matrix o_o*
@n0toose Although it doesn't archive anything, it makes the history browsable from a website, which is basically an anonymous Matrix client. I still disagree with them not honoring the "world_readable" setting, but describing it as an archive is wrong (but literally named it that, so...).