I'd certainly be a lot more interested in BMS if it had VR support right now, but it's just hard to go back to "flat" simming at this point. Cockpits were made for VR, plain and simple, and the tracking is so much better than TrackIR it's ridiculous.
That said, I understand why they can't just throw it into BMS. Falcon 4.0, even in its current overhauled state, is still running on an engine that is downright ancient by today's standards, not really built with modern graphics APIs in mind, and there's a very real possibility that simple things like clicking on cockpits will just not function correctly with a stereo 3D viewpoint, sorta like trying to use the mouse on the Elite: Dangerous galaxy map. That whole map, last time I played it, was rendered at entirely the wrong depth, way too close to my face, and it's jarring because of how well the rest of the game works in VR.
See, it's also not just a matter of technical reworking under the hood to bring it up to modern Direct3D11/12 standards as opposed to ancient D3D7 or D3D9; VR carries its own set of UI best practices, ones that Falcon BMS in its current state will most certainly not fulfill as long as the current menu system demanding an exclusive 1024x768 fullscreen mode is in place. Then there's all the radio captions and menus off to the side of the screen; that placement works fine on a monitor, but try that in a VR eye buffer and you'll find that you can't actually see it in the headset at all, because most of the periphery goes unseen in practice. That's why any VR screenshot showing the whole outlined eye buffer tends to have the HUD closer toward the center; that's actually closer to the edge of the viewer's FOV in the actual HMD.
These are just a few of the potential issues you can run into while trying to retrofit modern VR support into an old engine, and let's not forget that 6DoF head-tracking is mandatory at all times, no exceptions, lest you break immersion. That includes menus. On top of that, frame drops below 90 FPS are extremely jarring with VR taking up most of your natural FOV, which is why Timewarp/Spacewarp/Reprojection/etc. exist; they're frame interpolation techniques that fill in for brief framedrops based on user head movement, which while not perfect (it is interpolation, after all), help immensely with viewer comfort.
The ideal solution would be, quite frankly, to create a new, next-generation Falcon from the ground up, designed with VR, modern CPUs, GPUs and OSes in mind, but that kind of undertaking would require quite the dev team to get together and hack away at it. BMS is a volunteer effort, as I understand - people working to improve it in their spare time because they want to, not because they're getting paid to.