That's a very nice hack of github actions. The strength of that is to have super reliable storage but the risk is to loose everything because you don't respect the Github terms of use.
The relevant section seems to be "Additionally, Actions should not be used for...any other activity unrelated to the production, testing, deployment, or publication of the software project associated with the repository where GitHub Actions are used."
Don't get me wrong, I absolutely adore this usage of GH actions. But isn't this a TOS violation? I've thought about using GH actions as a generalized cron for online stuff and that feels like it walks the line (e.g. re-generating my static site via a Netlify webhook so it can update comments or whatnot). I feel okay about it because the static site is what's contained in the repo.
I've discussed this technique with GitHub employees about this technique in the past and no-one has raised any concerns about it. Maybe I wasn't talking to the right employees though.
Here is the term of use of Actions if anyone interested : https://docs.github.com/en/free-pro-team@latest/github/site-...