One of two things happens.

A) An algorithm flags your newly-created account as "inauthentic" and now you have to submit a copy of your driver's license to Facebook just to use a piece of consumer electronics you bought.

B) A different algorithm puts the pieces together and deduces that your burner account is the same identity as the real Facebook account you stopped using years ago or perhaps even "deleted." Nothing escapes the big-data inferences of The Graph.

I don't know... Facebook hasn't detected a single one of my 6 fake facebook accounts, and I've had them for years. I have been using one of them with my Quest ever since I got it, and they still haven't caught on.

Maybe I'm slipping through their net because my accounts are old?

Yes you are. They scrutinise new accounts much more now.

If you make a Facebook account and tie it to VR goggles, you’re not “not using it ever” but polar opposite of it...

The problem with this, is that all your purchases in the Oculus store become tied to that account. So then if you build up a library worth perhaps hundreds or even thousands of dollars (as I already have), you are running the risk of losing it all if at any point in time Facebook flags your account. The only narrow path to mitigating this is if you buy everything through SteamVR but that really hugely limits your options, and it's not at all clear to me it would not also run into problems as Facebook could easily associate your Steam account to your fake facebook account.

They would definitely connect the dots. Same home WiFi, for starters.

now that would be an interesting experiment to see how and if they figure that out

This also involves agreeing to the Facebook ToS.