zero
There are a lot of chances that could make a thing go into extinction and to some extent Bitcoin also can take place and at some point also we have to make such understandable and settled statements because, to a great extent, bitcoin is a much more stable asset and haven't existed for over a decade, it becomes obviously clear that Bitcoin any likely never reach that level of down level to the point of becoming extinct.
Bitcoin is here to stay and at that, we should get used to it and stop discussing its possible outcome at any point in time.
I feel the same way, the extinction is very small but it could happen, and I don't really care about that, because whatever happens I will follow it as long as it exists.