Aesthetic bug ??

Hello. Today i played minecraft on 1.17 for the first time. The designs you added are amazing and i find the new version amazing but i noticed something. It's not really a bug but a suggestion. I wanted to explore the ocean and i saw some land near the water. When i got there, i met a mountain that was ending right in the water. The thing is that the wall where the mountain ended was flat. It was flat flat, just a high wall made out of stone. I thought it was something normal because we do have these types of mountains on the earth but as i explored more, i found at least 5 mountains that had the exact issue. Some of them weren't even ending in the water.  i hope this helped! AND THANK YOU SO MUCH FOR MAKING MY LIFE BETTER! Minecraft is my favorite game of all the time and i really enjoy playing it! Good job guys. <33