I loaded up a world on the 1.18 pre-release 1 and went into spectator to explore. Underground I found a bunch of dripstone caves. This was normal, but as I continued to fly, there were more. And more.

I could not find a single normal cave in the area. Even the ravines and small cave entrances above ground were filled with dripstone. I used /locatebiome to find a lush cave, and the nearest one was 700 blocks away from me.

I don't know if this was intentional, but dripstone caves probably shouldn't be the default underground. They should be equal with lush and normal caves. 

The seed to reproduce this is for 1.18 pre-1: -5984335321648115322