OK, maybe we went too far with the word "dream," but Rosario would keep the Dodgers from missing a beat. And his numbers are probably right in line with what we expected of Lux, no? Over the last two seasons, he's hit .282 with a .722 OPS, 163 runs scored, 15 triples, 22 home runs, 128 RBI and 31 stolen bases. Plus, his defense is better.
You might be wondering why the Cleveland Guardians would even consider this. The most easily detectable reason is that Rosario will be a free agent after 2023 and the Guards probably aren't going to pay a mid-market shortstop contract to keep him. This organization loves to get all the value it can when these types of situations arise.
Additionally, all of Gabriel Arias, Andres Gimenez, Angel Martinez and Brayan Rocchio are on the 40-man roster and can play shortstop. Arias and Gimenez are the MLB options, while Martinez and Rocchio are top prospects making their way up the ladder.
Rosario could then be an extension candidate in LA, since he wouldn't command anything like Seager or Turner, in addition to the fact Lux's future is in as much doubt as it can possibly be. This might not sound like an earth-shattering move on paper, but the way he'd be integrated into the Dodgers lineup would fit like a glove.