I'm not super knowledgeable about it so I should just let someone else answer; but to clarify what I was saying, I'm not talking about the account migration, I'm talking about the fact that the new version ("education" edition, the one most kids use because of the steep discounts to schools) client can't connect to the old ("java edition") servers. The old server is still easy to run and hack on, but none of your friends will be able to connect to it, and while I don't know too much about the new server, all of the how-tos I looked at start with "go sign up for your free $100 worth of Azure student credits".
Maybe a clearer way to say it is, I'm not saying modding itself is harder, but I think that back when this article was written, if a teenager bragged that they run their own server with mods they usually meant they have a shell open on their home computer with "java -Xmx1024M -Xms1024M something.jar" in it and a mod directory with downloaded-and-hand-edited-textfiles, and nowadays they mean they pay for a cloud server and selected mods from a list. But again I'm mostly repeating what I hear from my kids' friends, tell me if I'm off base here.