You know what that is? It’s what it looks like when a great team have product market fit.
The execution of Tailscale is second to none. It’s pretty much a masterclass in making complex things seem simple. They’ve nailed onboarding, design, great documentation and just generally presenting an image of a company you want to do business with.
I realise this possibly isn't going to make me look any better than everyone else here to you, but have you actually tried Tailscale?
It does seem to be a near perfect solution for a few very specific problems, with almost no downsides and a user interface easy enough that you could do it without any knowledge of the underlying technologies