I guess that's the thing, though. Yes, mobile users should be using a bouncer — but who's going to set it up for them, who's going to host it for free and in a manner that it has guaranteed next-to-no-downtime?

It occurs to me that if IRC networks hosted their own bouncers, but that these bouncers were written efficiently to exchange data directly with the IRC servers' and their database rather than keep individual logs and so on, we might have something close to the "open-the-app-and-see-past-messages-without-needing-to-be-permanently-connected" quality that people have come to expect from instant messengers, Slack, Discord, etc.

(but then you might as well just write such functionality directly into the IRCd)