Really? Ambient occlusion used to be the first thing I would turn on. Anyways, 4k textures barely add any cost to the GPU. That's because they don't use any compute, just vram, and vram is very cheap ($3.36/GB of GDDR6). The only reason consumer cards are limited in vram is to prevent them from being used for professional and AI applications. If they had a comparable ratio of vram to compute, they would be an insanely better value compared to workstation cards, and manufacturers don't want to draw away sales from that very profitable market.