I have a Chromebook for testing, that has 8 GB of RAM, and in integrated GPU. It shows PBR and environments quite well. A good amount of testing we did for 2025 was done on MacBook Pros that have 4GB of VRAM. My new work Mac is 24 GB M4, integrated graphics. My work PC has 16 GB of VRAM.
The specs may be meant for people who are loading up their own 8k maps and environments. I think anyone using what comes with SketchUp should be ok with less VRAM.