But fundamentally, an acquisition of this nature is a simple build vs buy decision. In a situation where Tesla is ready to undergo a fire sale, its R&D will have already been cut to the bone.

If Tesla stagnates technically, "build" becomes infinitely more attractive; you're no longer desperately chasing a moving target, you're simply replicating what is known to work. Companies that can do this (as opposed to original R&D) are a dime a dozen.

If the company is still healthy, I just don't see who would have the means and motive to acquire it.