64GB is a good idea for multiple VMs.

Yes, if you’re running more than a couple lightweight VMs, 64GB is a sensible jump from 16GB. 16GB is basically a single desktop with a browser and maybe one VM. Once you add a second or third VM, you’ll hit swap within minutes and everything turns into a slideshow.

The math is simple: each VM needs its own OS overhead plus whatever workload you’re running. A Windows VM with 4GB is barely usable. Linux with 2GB is OK for light stuff. Two or three of those plus your host OS and you’re at 12-16GB before you even start doing actual work. 64GB gives you headroom for eight or ten VMs without micromanaging memory.

The only reason not to would be if your CPU is old enough that DDR4 is expensive or if you’re really only running one or two tiny containers. But for a real VM hypervisor like Proxmox or ESXi, 64GB is the sweet spot for a home lab.

Don’t overthink it. Future You will thank you when you spin up a test environment without checking free memory first.