Cave Biome generation by Temperature

If you go 20 blocks below a desert and find a lush caves biome, that does not make the most sense. This will only go until level 0 so layers below that generate any biome no matter what. Dripstone caves and lava Aquifers are in hot biomes, and Aquifers and Lush caves are cooler or damper. The chances of the correct biome temp generating with its corresponding temp above ground will happen most the time, 35% the time it will generate anything. So it is not fully affected by temp or less strict.