Mentioned this in the PL thread while trying to joke about United–Pool, but in the open source forum world it looks like Discourse has taken the lead over Flarum. It's also in use by a lot of big name clients for support forums, six times as many Github stars, etc.
Demo instances are snappy not that that means much, but there are decent guides for AWS hosting (Lightsail / SES) at a cost of around 10USD / mo, and some attention to migration though I didn't find much that was Flarum specific.
Anyway this is a bit of an annoying thing to post as I'm not putting my hand up to solve the problem, just saying it could be a decent path forward for OMITT if the bullet were bit.
