NVIDIA told PSU manufacturers their products need to be built to handle the RTX 30's transient spikes.
NVIDIA will tell them to deal with the current balancing on the PSU end.

This might change with RTX 60, but prepare for the worst and all.

With all this talk about PSUs, I wouldn't pay too much for a premium unit.
RMx or similar is a sane stopping point because Seasonic will be releasing new models with temperature/current monitoring & safety shutdown features for the 12V-2x6 connector on the PSU.
https://www.youtube.com/watch?v=ThwxImD4t98