I have been using it for a few weeks and really like it actually. It's much better than Github's old notification system, where I would click on something that I couldn't resolve there and then, it would get be marked as seen and I would inevitably forget about it. Now I am in control of what I see as done and I can easily unsubscribe from things I don't care about without unsubscribing from a whole project.

I also don't get on with Gitlab's system at all. Haven't tried git.sr.ht but this new Github design is way better than anything I have used before.