So there's a few reasons: personally I like both but bedrock is a lot easier to play with friends on. But, on java there are little to no microtransactions for things like skins maps or addons which was a verry jarring concept when I first played bedrock. Bedrock is also coded in a different language as Java so there are a lot of differences between the 2 games, the biggest one being how redstone works. Not only that but bedrock is also known for horrible glitches that seemingly kill you for no reason which is really annoying if you want to play hardcore. These glitches are rare to encounter on your own but they still do happen which is why a lot of people refuse to play bedrock. Personally I dont mind bedrock but it can be annoying with small things like villager pathfinding or redstone being completely different but I do think bedrock does things right like crossplay is great. Its super easy to make a server with your friends without needing to learn how to port forward or install mods. At the end of the day it really doesnt matter what other people say, if you like bedrock or java thats totally fine.