AFAIK, it will be possible to use SimulaVR either in standalone mode (with its own portable computer running everything) or in tethered mode (plugged into a normal computer which runs everything); there's even an option on the preorder page to get a version without the portable computer (it is my understanding that the portable computer is detachable, so the full version can be transformed into a tethered-only version simply by detaching it).

On Oculus, there's a way to skip the mandatory account sign in and just sideload apps instead. [1] Some tracking will still be there, but I think as it grows more popular we'll also see custom ROMs for it. Maybe even some running the Simula OS?

[1]: https://basti564.github.io/Quest-Account-Logout/