120hz enough?

I use a 540hz monitor, ive never owned a VR headset but I want one, but the highest refresh rate I’ve seen is 180hz on the 5ks which is outdated now.

Why don’t we have 240hz at least in VR??

Worried that going from 540hz monitor to a 120hz VR headset is going to negate the benefits of “immersion” and ruin the experience