> I feel that's a bit short-sighted, ... You can certainly do it, but you'll run quickly into issues and be buried in feature requests
(Disclaimer: i wrote 99%+ of the fossil chat front-end code.)
FWIW...
When Richard (our Alpha Coder) first posted about his proof-of-concept app for the chat feature my inner reaction was very similar to yours. However, writing a chat front-end sounded like an interesting way to spent Christmas, so dove right in.
Now, exactly 3 months later, we've been using chat 24/7 within the Fossil project and i use it heavily on one of my own projects (hosted over CGI, and my biggest initial skepticism was whether chat could work reasonably well that way). Despite my early doubts it's been a genuine help to us within the project. i don't recall us getting more than 1 small feature request since then, and that was cut off the same way the hypothetical deluge would be: point them to the feature's scope document and redirect such users to Discord or Facebook or whatever the cool kids are using these days.
It's been remarkably low-maintenance so far. The only notable development in the /chat code in the past 3 months was the recent replacement of window.fetch with more conventional XHR because of compatibility issues with window.fetch for some clients, and that took all of 90 minutes or so to do.