So if I understand this right, you pick a server and your server account can post on that server and any servers that that server federates with.
So what happens to your account if the server you joined goes down? Yes, you could always create a new account somewhere else, but you lose all your followed communities and post and comment histories as well.
The content from ALL is the same regardless of being from the same server or not. Yes, larger servers will have larger internal traffic so perhaps browsing will be faster. Small servers can still exist with few problems, especially if people prefer to only receive their subscribed posts.
ALL from Lemmy.world and ALL from other servers are not all the same. Each server has its own list of other servers which they federate with and some don’t necessarily federate with all the others. At least this is how I understand it and it confirms my observations and others have confirmed this as well.
This is true, which is why a solution will pop up maybe in the form of a website that could track what servers federate with what. People could choose a completely open server or a server that defederates the volatile ones.