PCIe scaling isn’t really significant. With a 4090 you lose 2% going to 3.0 instead of 4.0 at 1440p per techpowerup https://www.techpowerup.com/review/nvidia-geforce-rtx-4090-pci-express-scaling/28.html

He is using and instead of nvidia and linux instead of windows but his card is so much slower that the drop should be a lot less

From some other benches people have posted, ultra settings at 1440p he should be averaging 180 fps then even if he is using 3.0 x4 due to lane splitting from ssds which is roughly equivalent to pcie 1.1 x16 then it’s probably still not the main culprit

If you have a high end cpu its more price effective than other low end GPUs. The problem is needing a high end cpu kinda kills the budget argument.

Not terrible for their second attempt, but still not recommendable