On the MacBook Pro, the screen has a physical resolution of 3456 x 2234 but when you go to the System preferences, it says 1800x1169. This resolution is half the real resolution but MacOS manages this transparently, font rendering and other graphics rendering is done at 3456 x 2234.

I have the feeling this is not the case for tart/Linux VM (didn't test with MacOS VMs).
If I set a 1800 x 1169 resolution on the VM, the linux system renders for this resolution, resulting in blurry font rendering, in the console and in the Xorg/Wayland rendering.

Would it be possible for tart to pass this "true/physical" resolution to the VM?

Currently, the only way I found is to set the native MacOS screen resolution to 3456 x 2234. The Linux VM is fine then (at same resolution) but the macOS screen becomes unreadable, with tiny fonts (even if I use the 'accessibility' settings).