I kind of do that already with my most recent project, developing it in my local fossil repo and each release I have a script that copies it to a local git-repo, tags it, and pushes it to GitHub. So the GitHub history just has a series of release commits.

But the project is still open for issues and PRs. Can only be disabled on paid accounts, right? Never had anyone try yet. I had feedback through other channels, just not on GitHub, so maybe explicitly keeping all development offline has had the intended effect? I get a trickle of issues and PRs for my other repos where development is out in the open with every commit pushed to GitHub.

But if it was discovered by drive-by LLM contributors I would still have annoying extra work, for no obvious benefit compared to just sharing archives. I do not think anyone (out of at least dozens) discovering any of my repos do that on GitHub, but from seeing my posts elsewhere.

It's not like no one can fork a source code archive, even if it is like 3-4 git-commands to run instead of just a button to click.