On a laptop with an NVIDIA GeForce RTX 2060 Mobile GPU and AMD Radeon Vega Series (integrated) GPU, the NVIDIA GPU fails to initialize the internal display connected via DisplayPort (DFP-0). Despite detecting EDID data for the display (EDID version 1.4), DFP-0 is reported as disconnected in the Xorg logs. This causes X11 to freeze when initializing and prevents me from loading my window manager (dwm) or running any GUI applications.
Xorg logs also show that glamoregl and radeonsi are initializing userspace libraries for the AMD GPU, even though the amdgpu kernel module is blacklisted.
Arch Linux is not often solved in this part of the forums, you might want to search for similar issues in the dedicated Linux category. Make sure to read this post though:
That said, the most common issue in these cases is either that NVIDIA prime is configured incorrectly or that the Laptop BIOS works against proper HW initialization for the NVIDIA GPU to take control of the internal display. In that case disabling the integrated GPU in BIOS completely should alleviate the situation. Even if it might not be the desired outcome.