What if?
This will actually be the recipe for another Nuggets championship. Luka with Jokic, and Murray as the shooter, without MPJ in the roster anymore. It's actually a strong roster with the 3 stars healthy.
The NBA type of game doesn't play defense anymore, so yes, they could get a ring with that. The Nuggets played 7 games in the playoffs against the OKC. That means a lot, and adding Luka will get them a big plus.
It would be absolutely fantastic to see Dončić and Jokić playing in the same team. They would be a big contender for the championship. But I don't see any reason for the Lakers to let Dončić go. I also don't think the Nuggets have enough pieces for doing such a trade. This rumor doesn't seem very realistic to me. Of course, anything can happen in the NBA. Considering how Luka left the Mavs, you can't rule anything out.