If only there was a convention for storing PRs and issues and wiki inside the repository itself, similar to how Fossil[1] does it.
Then all the GitHubs and Gitlabs of this world would be limited to just providing UI and would be unable to hold our data hostage by design.
I've used git-bug[1] for issues and it works pretty well. The web-ui is lagging behind and PR support would be everything you'd need to ditch a central-hosted web instance.
I started using fossil recently and have been quite pleased with this aspect of it. I miss a few things from the git world (mostly magit and its magical ability to stage individual hunks of a diff) and there are a few rough edges, but I totally agree that having a wiki and issue tracking inside the repository makes so much sense. fossil‘s simplicity is a breath of fresh air for anyone who has to use git from a CLI. Well worth a try for anyone on the fence.