From their terms of service:

They (private repos) are also allowed for really small & personal stuff like your journal, config files, ideas or notes, but explicitly not as a personal cloud or media storage.

I’d guess that most private git repositories are small enough to fall under this category (unless you track large non-text files in git). This also seems like a very reasonable policy, considering that they’re a non-profit and they want to focus on supporting open source projects.

I’m using nebula to remotely access the raspberry pi in my home network and it mostly just works. The dual setup for nextcloud might be a bit more tricky, at least if you want to use HTTPS. You’ll probably have to set up a reverse proxy in Nginx for at least one of the routes, since they need different certificates (although since Nebula already authenticates and encrypts your traffic, HTTPS is probably not necessary there).

That can be a good solution at least if electricity costs are not a big deal. If power is expensive in your area, it might be worth to buy something more power-efficient, like a raspberry pi (assuming they’re not completely sold out right now).

No company is just going to host a server for you for free, a (virtual) server for running nextcloud will cost you at least a few bucks a month. As others have already said, you can run a server at home on your own hardware, but this is also not free (hardware cost, electricity, etc.) and you will additionally have to deal with any hardware issues & replacements yourself.

Honestly, instead of trying to remove Snap from Ubuntu, I'd just install another distro (PopOS for example is mostly like Ubuntu but with Flatpak instead of Snap)

Wie er es sich vorstellt, Atomkraft als “Überbrückungstechnologie” zu verwenden, verstehe ich auch nicht. Man bräuchte doch erstmal Jahre, um die Kraftwerke wieder auf Vordermann zu bringen und neue Brennelemente zu beschaffen. In der Zeit könnte man stattdessen auch einfach erneuerbare Energien ausbauen. Vor 10 Jahren hätte man darüber noch diskutieren können, aber mittlerweile ist die Entscheidung halt schon getroffen.