It seems in the time waiting for a response you could have tested this yourself already. But installs, is stable, and is supported are 3 different things.
That RPi 4 does indeed have 64-bit hardware architexture, but for the time being, the Official Raspbian OS is still 32-bit.
Effectively all apps still run in 32-bit.
From you can find on the net, there are plans for the Raspbian OS to make the switch to 64-bit at some point so that it can take full advantage of the hardware, and at that point we will be ready also with a arm 64-bit version of the SBC .
Mind you, we may not be supporting ESXi on Raspberry Pi. For the RPi we build the PBX/SBC software specifically tailored to be installed on the native OS and assume that all the resources are available to it.
If you end up making it an ESXi, then the resources will be split among X other VMs.