instances are like countries with their own constitution (rules) and police (mods). This means that two communities in different instances may seem the same, but they are not, because they have to follow the rules and culture of their instance.
Just like a Technology club in Japan will not be the same as the Technology club in the US because they will be culturally different. I think it will take some time for the Fediverse to think this way.
For me, this is better. Instead of having one giant technology community where your comments and posts are drowned out, we can have different technology communities with their own culture and norms, just like we visit different countries. Your comment and posts will be not drowned out.
It is a different paradigm to the centralised one of Reddit.