You cant apply the same generic logic to every situation in sports. The Cavs had already lost their last 2 Finals with LeBron in charge, and he had taken over control of the franchise with his choices in coaching and players. If he struck out a 3rd time, people would definitely be questioning the power structure in Cleveland. Its more than just "sad if we lose, happy if we win".
How can anyone doubt that if the Cavs had lost again, there would be some serious criticisms of the way things were going in Cleveland...
Who cares. Lebron has been criticized since day one. It's nothing new to him. And again --- getting to the NBA Finals 6 straight years is pretty special in my book. Criticize all you want if you don't win, but you are there year after year. And now he has three rings to show for it. I think his way is absolutely brilliant looking at his track record.