More startups should take this approach. Sure, they might need more styling/branding than you used, but this is so much snappier and accessible than the average SaaS product these days.
Yes, some of them have a case for local-first. If you do, you really should start with that out of the gate though.
While the tourney isn't going year-round, it has a demo mode where you can play through prior years (with friends! Or with yourself on another browser/device). The chat feature is admittedly half-baked and is mostly there to get my wife to quit asking about it. Will try to get that fully done for next year.
I'm also working on another side project in Gleam just to check it out. That seems to be taking shape and once I get something decent I'll post it.
All of these are self-hosted via Coolify on a VPS, which has almost been a project to itself (I've had it with cloud providers). I've learned a lot and it was cool to see some other self-hosting solutions in the thread here.
Yes, some of them have a case for local-first. If you do, you really should start with that out of the gate though.