When you remote into the Mac with VNC (which is the protocol Apples native Screen Sharing solution uses) you are limited to the display resolutions that the hardware thinks is available. This tricks the hardware into allowing additional resolutions that you otherwise wouldn’t be able to get over a VNC session.
This is just a completely foreign concept for Windows users. My main work PC is a laptop with a 4k built-in display, and 2x 1920x1080 external monitors. I can RDP in from my home machine, which has a single 5120x1440 monitor, with zero issues.
Only if you use RDP which is basically a remote graphic card where as VNC type systems capture the frame buffer of actual graphics card on the remote. Steamlink, Team Viewer, etc all have similar issues on Windows as well.
Tried doing Steam link to a Windows computer without monitor attached and would only work in like 1024x768, needed a monitor attached to get 1920x1080 almost bought a dummy for the Windows machine similar to this but had and extra monitor so I didn't bother.
Also VNC like system will turn on a monitor and you can see what people are doing remotely, RDP doesn't do that. RDP is a really nice system that gets really good performance over low bandwidth links due to remoting higher level graphics API, at least it used to, wish Apple had a built in equivalent that worked similarly.
Oh yeah, I know that RDP is superior. But Apple's own first-party remote desktop solution is basically VNC, and suffers from similar limitations. They could be more like Microsoft, but they seemingly don't care.
NoMachine is a great alternative for RDP. My remote desktop only had Win Home which have the RDP features disabled, so NoMachine is an answer to that. There is a command line to enable the RDP in WinHome but it require several step and external library to make it functioning. Now I have a new Intel NUC with WinPro, so I ditched NoMachine for MS RDP. NoMachine works flawlessly on macOS and Windows (and it have Linux support). I would say NoMachine is trailing behind MS RDP while Apple VNC is closer to the totem pole.
MacOS still uses the garbage VNC protocol instead of what Windows did, which was treat remote display as a first-class product; indeed RDP is one of Windows greatest features that is unheralded/underappreciated.
