That’s basically what I do right now except I do have a domain and my ISP doesn’t restrict inbound ports like 443 so it works fine.
Just trying to sort out if I want the headache of a VPS if I don’t need it (costs, maintenance, point of failure, etc).
Well, I mean it kind of is a solution. It’s a cloud backup solution. OneDrive doesn’t just keep a single version of your file, there’s versioning, retention policies, etc.
Cloud makes a lot of sense for businesses with small IT staff and a lot of users because while it’s not fully in your control, it comes with all the things being discussed here “out of the box” and scales infinitely.
For self hosters there’s some fun and power in doing everything yourself, but even then adding cloud as part of your backup (if done securely) is usually a pretty good idea.