Good morning, I hope you are well.
I come to report a world generation failure when it floods some caves if they are near rivers, small or large lakes and seas. In general, some of the caves, if they are not entrances to megacaves, are flooded from sea level, which is between layer 63 or 62.
This has made it impossible for me to enter caves quietly to mine materials since some do not have magma blocks that allow them to breathe for a while, and for the beginning of the game, spending materials on making doors is not a very good mechanic to go mining.
At the end of these flooded caves there is a wall that does not allow it to connect to parts where the cave is dry. This is a horrible early game disadvantage. Forces the player to search for entrances to megacaves or ladder mining down for resources.

This generation problem does not affect very dry biomes such as the desert or the badlands. Since the number of rivers is a little minimal and the same with the lakes. Even so if they are close, they are flooded.