I do agree that the game isn't in a good spot for servers at the moment, but both 1.15 and 1.16 have included lots of optimizations. I'm sure they know about the issue and are slowly moving towards more server friendly code.
Well I lurked on PMC for about a year, hoping for datapacks that would fit my interests. Some did but they had a lot of design takes that I disagreed with. I thought I'd just teach myself and make the features I wanted myself haha (I've always been more of a builder/writer)
That's true! Bedrock''s add-ons are improving. But Bedrock simply doesnt have the breadth of customization that Java has. Java has near unlimited control and content to choose from. Everything Bedrock can do in terms of customization, Java can do and more.
Java Edition is like an Android phone. Lots more features and customization that you can do yourself. You can modify and dig into the files however you want. Bedrock is like iphone. It looks prettier and is more streamlined. Its decent for newer players, but if you want the full Minecraft experience I would recommend Java Edition.