You're not forced to use a feature if you don't like it.Sorry but that's a terrible idea.
I don't think there is anything more disorientating in the game as when trying to do a loop in the SRV, and when you get to the top it makes you look to the side and then does some twist/flip with the camera. That forced perspective change, which is even worse if you screw up and are tumbling down a hill, is a stupid design. How that's supposed to be less nauseating than just making a smooth loop is beyond me. The only thing that makes it worse is having black out on and having the scene go black right as you are pulling out of the loop. Just close you eyes instead.
As for doing a roll, what's the point of it if the horizon stays right side up when the SRV is upside down? If you're flying an SRV and roll, then the horizon should roll, not having the SRV roll around you. The feature doesn't make rolling harder, it may even be easier, but it takes the fun out of performing a roll. I can't believe this is a feature in any flight sims, even the arcade ones.
I did some testing today to remind myself how things looked. When doing normal driving and flying, using the vehicle maintain horizon camera feature really makes it much nicer. You can just bounce over the tops of the moguls, with the SRV rocking and pitching while your view out the cockpit window is nice and smooth. But once you boost up into the "air", and once you start rolling, if the horizon held for 10-15 degrees, and then started following you around the roll while you go upside down, I don't see how that would be so jarring. I tried imaging it, but it would take testing to be sure. It wouldn't need to snap instantly either as it could transition. And then do the same thing for loops, maybe after a larger angle change, and get rid of that camera flip at the top of the loop.
Maybe head stabliization is the wrong term as it doesn't affect your looking around in VR, but that's basically what it's doing. It's like riding a dirt bike and your body absorbs the bumps, with the bike bouncing around below you while your view over the handlebars is relatively smooth. But if you force a roll or loop, you actually roll or loop like you're flying your ship.