Appreciate the answer, thanks. I guess that would rule out the people who definitely do not even want the possibility of the prospect of maintaining their own engine. I would be curious to know what kind of percentage we would be talking about...
No engine is guaranteed to be maintained, not even the UE/Unity. Look at CryEngine, once a big, popular engine. Now with all the CryTek's problems, I would not bet it won't get dumped.