It's almost like the requirement for "true" ownership is the ability to defend it.

If people want to be so pedantic about taxes, then sure, you don't technically own the land because you are not in control of a country with a private army strong enough to protect it.

This is why some people buy boats. Once the boat is paid off that's it. They can't tax the international waters around you. Problem solved. With Starlink coming soon you'll even be able to get decently cheap internet too.