I have PRs open on five different OSS projects at the moment. My throughput is being limited by trying to remember all the details of PRs I filed 3-6 weeks ago.
I thinK I have to admit to myself that as little as I like github having all the projects, I'd be less effective having to track inboxes across half a dozen different hosting platforms.
If you made something like Mastodon, where alerts propagate across instances, I could probably deal. But without that? No, I'll pass.