But at the same time, for any new users who value their own privacy the device is now pretty useless, and for any existing users who value their privacy but also want to be up-to-date and get new features, they're also probably going to be locked out in future updates.

So you kind of have to excuse them for focusing on the negatives, because they don't get to enjoy the positives. It's kind of a moot point for them what Facebook brought to the table.

This is always the concern with these kinds of purchases, and I think this was a big part of the concern back in 2014. I was never worried that Facebook wouldn't invest in Oculus, as a consumer I was worried that it would ruin the Oculus ecosystem and shove dystopian adware onto the devices.

Can't help but think of this comic: https://www.newyorker.com/cartoon/a16995

Why does this have to be true at all? Let bad things be bad, and deal with them. Don't try to rationalize away problems.

One notable thing is that Oculus hired Michael Abrash just following the announcement of the acquisition. With John Carmack, who was already there, they are among the most (if not the most) prominent developers in the field. Even though Carmack stepped down as a CTO, both are still there. I have stopped following VR news but Oculus had pretty nice prototypes a few years ago which combined eye tracking, foveated rendering and varifocal lenses, all addressing fundamental problems with the current generation of headsets.

Also, even though I am not sure about Facebook involvement, they financed some of the best VR games at the time. Lone Echo is one of them. Ready At Dawn, the developer is now part of Oculus Studio, a branch of Oculus focused on making VR content. Note that having good VR content is extremely important, even more so than the devices themselves. I mean, you are not going to spend hundreds of dollars just to slash cubes, or maybe you do, can't blame you ;)