I'm trying to generate a void world with the default overworld biomes using a data pack (attached). I've managed to strip the world of most detail, but when it comes to doing this: "default_block": { "Name": "minecraft:air" } (in data/minecraft/worldgen/noisesettings/overworld.json)

The world generates with stone blocks water lakes. It should probably be noted that, when generating the world for the first time, I change nothing in-game. I simply rename the world, select the data pack, and hit generate.

There are other problems, like the fact that there shouldn't be any lakes at all, and the fact that a bedrock floor generates when it shouldn't, but I believe those belong in separate bug reports.