The fact is the Tesla statement "almost all circumstances" is ambiguous, and probably intentionally so. Does it mean "can drive where a human can drive, but not in extreme cases where even a human would not drive", or does it mean "can drive the majority of the time, but in some unusual cases a human may have to take over" ?
The first definition suggests L5, while the second suggests L4. I don't see any way to determine which Tesla mean by "almost all circumstances", since they do not clarify the statement anywhere that I can find (I dont count Elon's tweets as formal statements).But I'm willing to bet that if it came to arguing over this in a court Tesla would lean to the L4 definition if it were a case of liability.