I use Proxmox/virtualisation because I want to be able to run services within their own OS. I've got a VM dedicated to docker both at home and in my colocation, since a lot of services I'm happy to just chuck on there, but there's others with more complex setups, and other services/systems that just running them in docker isn't an option.

I'm using a commercial desktop with an i5 Sandy bridge. I maxed out to 32Gb of ram only because I'm running trueNAS, debian with containers, and home assistant. Most RAM goes to trueNAS and trueNAS doesn't accurately report ram. For CPU, mostly just task limited but I don't really think thats a proxmox issue. Obviously it's not going to support an enterprise or even small business but it works for what I need of less than 4 users on my budget.

Proxmox doesn't really ask for much but I probably would recommend docker for your arm devices.

I use it on reclaimed hardware ... Works great for me. Has all the features you'd want for a home lab, and I run a few production hosts there as well

It seemed nice at first, but one major issue: GPU passthrough was a nightmare. It cant be done in the UI and I didnt understand fully how it worked. There are many different tutorials not by promox that are outdated or may not work. It was frustrating enough I jumped to NixOS. Other hiccups included having to go to the terminal to passthrough drives for openmediavault, but that one was kind of straightforward atleast, and it worked first time.

In hindsight, I didnt actually need to virtualize everything at that level, so I never really had a good use case for it anyway. I use containers over entire VMs.

You need Proxmox

Seriously though it is nice to have