When you run VM, you assign part of resources of the main machine away, obviously. If you need all resources often, running in VMs can become annoying and slow you down. Also, assignment is not necessary dynamic on some resources (cpu) so even idle VM can slow down the rest.
In my case my MBP is generally enough even when fraction of cpus are assigned to VM, so I am fine. Will you? No idea.
One note is that if you plan to run full blast any M4/M5 machine all the time, you should get desktop. At full blast battery life of the MBP or Air is not going to be that great. I occasionally use 40+W of power on my M1 MBP when I run some hard tests. Rarely, so I do not care that much, but with 40+W draw MBP will have only ~2.5 h run time, kind of my previous Intel MBPs when used for anything useful ;-)
