I'd be fine with an update that brings beams that can tear apart, even if that's the only contents of the update (and not predetermined break groups). It's been the main limitation of the engine for years, that and giving objects around maps their own jbeams Doubt we'll see it until rigid body physics become a thing lmao
Technically it's super easy to do in theory, but practically if you try you could get all sorts of random unpredictable issues everywhere on normal crashes, it would depend on the car of course, I could try making a mod that does that so you can see what would happen if it was official
I do recall the developers stating why it hasn't been put into the game yet, being the glitchy nature of mesh tearing and objects once separated tending to react glitchily when interacted with. Not sure if the latter problem has been improved upon over the years with the game engine, but that doesn't matter if it makes a spiky mess of the mesh.
Hasn't been improved at all, BeamNG still uses the same basic mesh interpolation algorithm as it has used since the start, maybe it's about time they used a more advanced one now