Well I seemingly wrongly assumed you were one of those "ARM will take over the world" guys. About 10 years ago even Anand was talking about x86 in iphones. Clearly that never happened. Meanwhile we have had people talking about ARM taking over x86, and that has yet to happen. There was a similar RISC vs CISC debate in the 90's, and we all know how that turned out.
If after 10+ years we haven't seen x86 on mobile or ARM on PC's, I have to think they are both the best at what they do in those form factors. Maybe we will see an ARM uprising within five years, maybe not. I would bet against it though. Sorry if I misunderstood you as an "ARM everywhere" type.