Basketball is a team sport and as such, you can't expect to win on your own. No one, not even Michael Jordan or Bill Russell could ever single-handedly win a ring, and LeBron James isn't the exception to that rule.
LeBron James has had his fair share of top-notch teammates to win a with, such as Dwyane Wade, Kyrie Irving, Chris Bosh, and Kevin Love. That's why Anthony Davis' injury is terrible news for him and the Los Angeles Lakers.
In fact, former NBA champion Richar Jefferson went on record on Sports Nation to say that Davis' injury is going to cost LeBron James the MVP award of the season and more importantly; the chance to win back-to-back rings:
“Anthony Davis is the key to the entire NBA. He allows Bron to be the MVP. If he’s not a 100% healthy then I don’t know if they repeat and I think you have to start looking at the Clippers and the Brooklyn Nets, Jefferson said.
That's a valid point right there even if it sounds like a bit of a conspiracy theory. But yes, Davis is the first domino in the NBA status quo. Without him, LeBron James can't play at the same level in the Western Conference, thus conceding his status as a leading MVP candidate.
Moreover, the Lakers would no longer be the team to beat despite being the reigning champions, meaning that the throne is up for grabs. So hopefully, for him and for the purple and gold, Davis will be able to come back rather sooner than later.