Since negative Y levels are now a thing, I expect commands that only accepts positive Y levels in the past
now works on negative Y levels too. Makes sense.

So I expected /spreadplayers under to support negative Y level coordinates now that it's a thing, but it isn't.

Command used:
/spreadplayers ~ ~ 0 0 under -20

Here's what happened: ("Integer must not be less than 0")

Should this work for all Y levels now that negative levels are a thing in vanilla survival?