I am in no way even slightly an "expert" here, but Incus could be considered a lightweight Proxmox..
They're both going to run some VMs and / or containers, but with Proxmox you get the overhead of the fancy GUI.
So if your host(s) aren't running guests at >90% load, then there won't be any difference in performance.
I've recently installed Proxmox because everyone else uses it (and VMware's free ESXi is now dead)... but after pulling my hair out trying to get some things done, I'm seriously looking to move to Incus.
There's another post here somewhere (the one about free ESXi being killed off) with someone explaining more about Incus, which seems like it's the way to go... maybe worth a search.