Now if you want to bring up media exposure and endorsements you have more ground to stand on. Obviously you become a better player in the medias eyes when they see you every night. Even if that is not the truth. Trevor Ariza gets more attention then Bruce Bowen but he is not the same quality defender.
The thing is if your team is not winning, no one cares. Ask New York. Who is the last big name player to run to New York for those reasons? Kevin Garnett went to Boston because he thought he could win. His And1 and Gatorade commercials were flying in just fine when he lived in Minny.
Things have changes since the 80s and 90s in terms of player endorsements. If the players are big enough, it doesn't matter. That is why KG always did gatorade commercials. Why Dwayne Wade does T-Mobile commercials. Why Charles Barkley did Right Guard commercials while in PHX. Has Shaq's endorsements dropped off since he left LA? Not really. I see him doing Crunch, Icey Hot, Vitamin Water, etc.