Has that been announced? Or is it more a matter of Intel producing some unannounced product on an unannounced timeline with a feature set that has yet to be announced on an architecture that may or may not involve arm? Intel walking away from x86 would be a big step for them. First they don't own arm and second all their high end stuff is x86.
They will be manufacturing them for their customers.
Also arm isa is just isa
You seem to focus on it too much when it isnt THAT relevant.