A better question: why does a VR headset require an account at all? Should my monitor require an account? Should my keyboard?

It's a peripheral, not a platform.

I'm sure this just changes which pipe usage data goes down, but this means Facebook directly gets to use your VR usage/purchases to market to you, and they will follow you around the web, because they know. I think that's the main reason folks generally dislike FB connect in the first place, but I don't want to speak for everyone :)

Forcing users to violate their personal moral principles, upon which the decision of never using anything related to Facebook rests, is a big enough difference for many--myself included.

EDIT: I didn't know that Facebook bought Oculus some time ago, back in 2014--for some reason I thought it happened far more recently. I would make the case above for someone who had bought an Oculus device before Facebook's acquisition and now would be forced to use its platform, then. I don't have anything to do with Facebook, personally. I don't even use WhatsApp, so there's that for my moral integrity.

I'm not sure if you mean "an oculus account owned by Facebook anyway" - but in general terms I'd be somewhat surprised if a "real" game/software/service company (eg: Nintendo, gog.com) kept quasi-/il-legal shadow profiles that they actively tried to pair with your account.

On Facebook you're required to use your real name. I don't know if the same is true of an Oculus account, but that's a major difference if not. Of course you can create a Facebook account with a fake name, but then you risk getting banned.

Can you do so without accepting their terms of service? They use every data source they can to build profiles for people so accepting the ToS is going to approve use of your information for as much as they can get away with.

I do not like the idea that I need a social media account to use a VR headset, regardless of the realities of using the oculus account data still ending up with facebook.

because every action you perform within the account that signs into the FB account becomes a parcel of information you're giving to FB.

If you sign in to one of their accounts, you are functionally signing into the facebook website.

What if you are not allowed to make a FB account due to their TOS? Not everyone can be on FB.