Not entirely sure why this reply is being panned (was at -6 when I first saw it).
OP is in the process of upgrading their PC to a Ryzen 9. If we make the assumption that this Ryzen 9 is on the AM5 platform, the CPU comes equipped with an IGPU, meaning the RTX 3060s are no longer needed by the bare metal. So, installing a stable, minimal point release OS as a base would minimize resource utilization on the hardware side. This could be something like Debian Bookworm or Proxmox VE with the no-subscription repo enabled. There’s no need for the NVIDIA GPUs to be supported by the bare metal OS.
Once the base OS is installed, the VMs can be created, and the GPUs and peripherals can be passed through. This step effectively removes the devices from the host OS – they don’t show up in lsusb or lspci anymore – and “gives” them to the VMs when they start. You get pretty close to native performance with setups of this nature, to the point that users have set up Windows 10/11 VMs in this way to play Cyberpunk 2077 on RTX 4090s with all the eye candy, including ray reconstruction.
Downsides:
Three operating systems to maintain: bare metal, yours, and your partner’s.
Two sets of applications/games to maintain: yours and your partner’s.
May need to edit VM configs somewhat regularly to stay ahead of anti-cheat measures targeted at users of VMs.
Performance is not identical to bare metal, but is pretty close.
VM storage is isolated, so file sharing requires additional setup.
Upsides:
If you don’t know a lot about Linux, you’ll know a bunch more when you’re done with this.
Once you get the setup ironed out, it won’t need to change much going forward.
Each VM’s memory space is isolated, so applications won’t “step on each other” – that is, you can both run the same application or game simultaneously.
Each user can run their own distro, or even their own OS if they wish. You can run Fedora and your partner can run Mint, or even Windows if they really, really want to. This includes Windows 11 as you can pass an emulated TPM through to meet the hardware requirements.
Host OS can be managed via web interface (cockpit + cockpit-machines) or GUI application (virt-manager).
It’s not exactly what OP is looking for, but it’s definitely a valid approach to solving the problem.