You make a good point. But I still find that directly exposing a port on my home network feels more dangerous than doing so on a remote server. I want to prevent attackers sidestepping the proxy and directly accessing the server itself, which feels more likely to allow circumventing the isolations provided by docker in case of a breach.
Judging from a couple articles I read online, if i wanted to publicly expose a port on my home network, I should also isolate the public server from the rest of the local LAN with a VLAN. For which I’d need to first replace my router, and learn a whole lot more about networking. Doing it this way, which is basically a homemade cloudflare tunnel, lets me rest easier at night.
Can confirm that there is 0 ingress or egress fees, since this is not an S3 container storage server, but a simple FTP server that also has a borg&restic module. So it simply doesnt fall into the e/ingress cost model.