I think we'll see a lot of ARM use cases outside of the Apple stack and x86 is dead (but it will of course take its sweet time getting there). For the longest time everyone believed at a subconscious level that x86 was a prerequisite due to compatibility. Apple provided an existence proof that this is false. There is no longer a real need to hold onto the obsolete x86 design.

The only way for Intel and AMD to thrive in this new world is to throw away their key asset: expertise in x86 arcana. They will not do this (see Innovator's Dilemma for reasons why). As a result they will face a slow decline and eventual death.