These are the records of the teams before LeBron arrived:
Miami Heat - 43-39
Cavs - 33-49
Lakers - 35-47
He made them into "good situations" and then left when they weren't anymore. I don't see anyone knocking Jordan for retiring in 1998 when he saw that the Bulls were going to become a shitshow. Instead, he's lauded for it. Lebron encountered the same problem, just multiple times throughout his career.
The guy reinvented himself to play with all kinds of players, whether they're ball dominant like Wade and Kyrie or big men for a new era like Bosh and Love. Maybe he doesn't get extra credit, but there should be some context applied when comparing him to Jordan. Like
@lovegtm says above, the only real difference is that Jordan found his Pippen during his prime and Lebron had to seek that guy out because the Cavs we're busy supplying him with Donyell Marshall. If that kind of superteam building should be viewed as a "cheat" or a "shortcut", then let's take that same view of the 08 Celtics because KG would've never accepted a trade here if Allen didn't come first.
I think people would have a different perspectives on this if Lebron didn't make an ass out of himself during the decision and Davis wasn't such a jerk when he left New Orleans. In a vacuum, both players making their way out of ridiculously inept organizations would typically be celebrated (see: any free agent who signs with the Patriots).