Enterprise computing is like competing to be the new mainframe
Why the fuss about enterprise server applications? They might matter to VMware, but they are a diminishing proportion of computing. ARM AArch64 might be able to run enterprise applications, but why would a ARM chip manufacturer go up against Intel with a high power, high throughput chip when it could make more certain money with a low power design.
What AArch64 will do is to totally win the "appliance" space, as those little 1RU boxes which do useful things will have less power draw (and thus heat issues, and thus be cheaper to design and own and be more reliable). Those appliances pretty much all run Linux, or will.
AArch64 also has a decent run at a peculiar sort of desktop -- the space which used to be filled by the "IBM mainframe terminal". Low power -- with its reliability and a small size on the desk -- makes ARM more attractive than x86.
I doubt ARM has much hope in the cloud, as it's performance per watt still trails x86 at maximum throughput. Remember that cloud servers are provisioned to be either at maximum throughput or to be off. If ARM is used it will be because cloud providers specify their own CPU, and obviously AArch64 is available for that, whereas x86 is not.
There's plenty of opportunity to make money with ARM servers without going for the hardest market first. The only attraction of enterprise is the large profits available due to their poor management of computing. But that very same poor management makes them adverse to change.
Biting the hand that feeds IT
