One reason you're noticing a homogeneity of opinions on here is the fact that Lemmy isn't botted like larger social networks. Larger networks have bots farms pushing all sorts of narratives for various reasons, and the one thing they accel at is finding people to argue with.

You are also certainly in a bubble on Lemmy. You have to know it exists and care enough to use it over other platforms. Most people choose the path of least resistance.