I guess there must be a fallback of sorts. Either that or the game crashes at some point.

The 2060 6GB was the minimum spec recommended by Remedy so the results seem as expected. There doesn’t seem to be a massive performance delta between the low preset and the high preset (without RT). The 5700XT can’t maintain 30FPS on low, but the 2060S looks like it can get a solid 30FPS lock (or perhaps 40FPS with DLSS).

Some people need more VRAM than others.