I think the term universe shrinking can’t really be applied to Star Wars and Empire. What you criticize, is that they don’t establish a very vast universe, but universe shrinking means that the established world is retroactively made smaller. Leia being Luke’s sister has consequences for the other movies before Jedi, while not offering anything interesting to the plot. The Yoda subplot is interesting enough on its own, so most people don’t care about the setup being too convenient or not.