I seriously think people are gonna get raped in the ass by the 3070 is they buy it for 4k or downsample.
My 8gig in my Vega is on the edge now and that's HBM2.
This is not taking into account the most important element limiting 4k performance which is not memory capacity but memory bandwidth. 2080 Super is on 256 bit bus and 2080 ti is on a 352 bit bus.