in minecraft 1.17 betas 1.16 world biomes is dont generating

in the betas when caves and clifts activated or when not the world isn't generatin 1.16 and below biomes like plains and other biome and structer generating is very rarer so you can find 1 single village in entire 1000x1000 area and there no cave enter so i traveled more than 4000 block in my minecraft survival world and i didnt never found single cave enter and a biome from 1.16 and below it just a new mountains and underwater caves ihave never seen before so please fix this add the old biomes again and readd the old caves becau there is only new caves