The future of selfhosted services is going to be… Android?
Wait, what?
Think about it. At some point everyone has had an old phone lying around. They are designed to be constantly connected, constantly on… and even have a battery and potentially still a SIM card to survive power outages.
We just need to make it easy to create APK packaged servers that can avoid battery-optimization kills and automatically configure an outbound tunnel like ngrok, zerotrust, etc…
The goal: hosting services like #nextcloud, #syncthing, #mastodon!? should be as easy as installing an APK and leaving an old phone connected to a spare charger / outlet.
It would be tempting to have an optimized ROM, but if self-hosting is meant to become more commonplace, installing an APK should be all that's needed. #Android can do SSH, VPN and other tunnels without the need for root, so there should be no problem in using tunnels to publicly expose a phone/server in a secure manner.
In regards to the suitability of home-grade broadband, I believe that it should not be a huge problem at least in Europe where home connections are most often unmetered: "At the end of June 2021, 70.2% of EU homes were passed by either FTTP or cable DOCSIS
3.1 networks, i.e. those technologies currently capable of supporting gigabit speeds."
Source: https://digital-strategy.ec.europa.eu/en/library/broadband-coverage-europe-2021
PS. syncthing actually already has an APK and is easy to use. Although I had to sort out some battery optimization stuff, it's a good example of what should become much more commonplace.
IMO, more like Linux. Android for such old devices is unmaintained, but if you're able to run Linux on it you'll still be able to apply kernel updates and security updates for software will continue to exist. Many things are opensource too and you should be able to recompile them on the android device to make it run.
PostMarketOS or UBPorts are basically that, but have limited functionality and few hardware options.
Seems like this is a great use-case for an RPi. At least for single/few user setups