HiDPI options are normally only seen on HiDPI monitors. Are you sure that your Aorus monitor is a HiDPI display? From what I can find on the internet, it's a 2560 x 1440 27 inch display.
That said, the resolution options are a bit strange: there is no 2560 x 1440 option for example.
You can sometimes get more resolution options by holding Alt (option) when ...
I use the excellent software Pacifist to tell which files are installed from which source.
You can also just make a new Volume and install a clean version of macOS to see which files result from a clean install with no migration.
Catalina introduced a new feature that overlaps and reinforces the filesystem protections that SIP provides. What it does is split the files between two volumes: a system volume containing Apple-provided system files, and a "data" volume containing all non-Apple and modifiable files. The system volume is mounted read-only as / (the root filesystem), and the ...