Your view with what happened with Itanium isn't what really happened. There is a wonderful talk by Bob Colwell (architect of the P6 / Pentium Pro) given for the Stanford EE380 course in 2004 titled "Things cpu architects need to think about". Sadly it looks like all online copies have gone. I very highly recommend the whole talk if you can find it.
Itanium was supposed to take over everything, not "enterprise". Amusingly its performance projections were based on 36 hand coded instructions from a representative inner loop in Spec, and management went ahead based on that. Even though they would leapfrog x86 in theory, in practise x86 did a steady march in performance improvements (helped by Intel's fabs). As Itanium got late, rather than cancel the project, they decided x86 was for the masses and Itanium for enterprise.
I really like that they are trying Mill, but suspect Risc V is going to soak up the dollars and attention.