Structure generation options ignored in superflat presets (previously fixed issue)

Using the following preset has different results in 1.15.2 and 1.16. This seems to be the same issue as these from 1.13: MC-132362 and MC-131749

The preset:

minecraft:bedrock,200*minecraft:stone,2*minecraft:dirt,minecraft:grass_block;minecraft:plains;village,mineshaft(chance=0.8),stronghold,oceanmonument,biome_1,dungeon,decoration,lake,lava_lake

Screenshots - imgur link, I couldn't upload them here due to error (Jira could not attach the file as there was a missing token)