The driving force behind people not wanting to play for those teams is cause that's players don't see futures for those teams, especially immediate futures. Knicks and Lakers have all this money and off-court opportunities, but nothing basketball related, especially winning. Melo is clearly fine with getting paid and losing at his age. LMA clearly doesn't want big money and L's. If he did, he wouldn't stayed in Portland, or went to LA. No one is afraid to play under the bright lights of a washed Kobe in LA or a demotivated Melo. It would be silly to hitch your hopes to either of those
Off the court opportunities are overrated anyway. Guys with huge endorsement deals are in small markets now. Lillard, Russ, KD, I'm sure Wiggins will get his, AD, etc. The endorsements and everything is there as long as they see star power.
This is true to a certain extent. CP3 really didn't start getting the good ads until he went to LA, maybe the same for Melo?
It can be a added bonus.