The biggest reason I find git submodules painful: a "commitlink" object in a git tree does not count as a reference to that commit or anything that commit refer

The biggest reason I find git submodules painful: a "commitlink" object in a git tree does not count as a reference to that commit or anything that commit references, for the purposes of garbage collecting the repository or pushing and pulling changes. You can't have the only reference in your repository to a given commit be a commitlink within another tree. I'd like to jettison the entire model of "reference another repository that you may or may not have", along with the `.gitmodules` file as anything other than optional metadata, and instead have them be a fully integrated thing that necessarily comes along with any pull/push/clone.