Here is what I tested as a max, Real world testing of 12v vs 24v - #14 by vicious1, 12v Z 4 start 63mm/s, 24v 4 start 80mm/s with stock screws and accel. Z accel is very low, but needs to be.
So with 4 start screws you will get 4x’s slower than XY, with 1 start 16x slower, 2 start 8x slower.
Steppers are just not high speed motors.
With less start screws you can get higher accel, so in the end they might be quicker for tiny moves, but 4 start will always have higher top speed.