A lot of them also restrict content. There are disadvantages to joining smaller instances, depending on the philosophy of the person who runs the instance. There's even an instance that does not allow communities to be created on its own instance. It will accept applications from people who wish to create one, but they mostly reject applications on their own whim. I think the future of Lemmy as a Reddit alternative will rely on larger, freer instances to be supported well so they have room for growth and change. I have my personal preferences. I don't want content from exploding-heads, but I also want to see the content I want to see. Some smaller instances are restricting that content, almost seeming to be like cults in the making. There are small instances from which it is impossible to find and subscribe to communities from lemmy.world. You have to search for them on a larger instance, then copy and paste in the address bar in your browser. I imagine on a dedicated phone app that would not be possible. So, you can advocate for "spreading out" all you want. In the end, if the goal is to have a strong alternative to Reddit, spreading out is kind of pointless for a lot of users.