>nobody is going to say "but we've used Intel for a decade, how can we suddenly switch to AMD?!".

Maybe not those exact words, but people will say "We are adding a server to our VMWare ESXi cluster, so if want it to be compatible with our existing hardware we better stick with Intel."

VMWare's high availability feature (a highly desired feature for any data center) won't work across different CPU architectures, so unless you are replacing your entire stack and not just adding server(s) then you have to stick with the architecture you already have in place.