Soul fire patches cannot generate in the nether wastes biome despite being included in the biome's features

Soul fire does not generate in the nether wastes biome on top of soul sand.

Steps to Reproduce:

1. Create a world, and go to the nether wastes:

   /locate biome minecraft:nether_wastes
   

2. Fly around and try to find soul fire inside the biome

Expected Result:

You would find soul fire, because it is included inside the possible features which can generate in a nether waste biome:

Observed Behavior:

You will never find soul fire in the nether wastes, despite there being soul sand patches around.

Screenshots/Videos:

The cause of the issue, where the feature only generates on soul soil:

Notes:

1. This issue was first reported with reproducing the issue in a buffet world, but these kinds of worlds are no longer possible to make.