Re: Is Linus's vision really this narrow?
I think we can assume that Linus is talking mainly about the world of servers and data centres, where ARM is just a rounding error.
x86 has the advantage of the various ISAs (industry standard architecture) over the years that has made investment in it as a platform less risky: chip manufacturers aside, there are lots of suppliers for the rest of the kit. ARM is still chasing this kind of uniformity so that moving from one ARM-64 box to another requires more than just recompiling.
However, the sheer volumes of ARM in personal devices has goosed development to levels beyond those that Intel can match and competitive server products are now becoming available. Initially it might only be bespoke hardware for some of the private data centres such as those of Google and Facebook or CDNs like Akamai and Cloudflare, but we can probably expect more generic products as more experience is gained in the field and manufacturers see real cashflow.