In both of these world saves I made, the Nether is generating like the old nether terrain but still with biome specific blocks. No crimson or warp trees spawn, or their grass equivalents. the vines however are generating. The basalt deltas are not generating the crazy spike pillars or their lava pits. They all are using their biome specific block. I am not sure this could be my Minecraft or if it is something everyone else is experiencing. Just noticed it playing a survival 20w45a and thought it was weird their was no trees where my portal started at. Went and made another world to see if the issue would occur again and it did through out all biomes.