Potential lottery ticket win, they are available for consulting internally anywhere that can add value, and they're not working for anyone else.
I believe low wattage SOCs can make traditional desktop hardware irrelevant (ish), but I think ARM is orthogonal to that.
The thing is, x86 dominance on servers,etc has been tied to what developers use as work machines, if everyone is on ARM machines they'll probably be more inclined to use that on servers as well.
It's like an avalanche effect.
The main reason x86 still has relevance and will continue to do so is because x86 manufacturers actually care about the platform and their chips. x86 is somewhat open and standardized. ARM is the wild, wild west - each manufacturer makes bespoke motherboards, and sockets, and firmware. Many manufacturers, like Qualcomm, abandon their products remarkably quickly.
A company sufficiently scaled can largely only be fixed by the CEO, and often not even then.