And another angle, if you want to store a snapshot of a repo on IPFS https://github.com/whyrusleeping/git-ipfs-rehost
Can one simply place a git repo in an IPFS directory (e. g. with some IPFS fuse implementation) and share an IPNS / DNSLink so that future changes can be found under the same address?
In this aporoach github issues and pull requests can be replaced by discussions and patches in a mailing list.