Villages generate in superflat void worlds

If you create a super flat world and remove all the layers so you end up with a 100% void world, then villages can still generate in the air. Crops, flowers, houses, everything float, and the villages fall into the void.

This affects version 1.16 and above from my testing. Prior to that, in 1.14-1.15 it is not possible to create a void world this way, it keeps the grass in.