This is nothing compared to the fact that they are more likely to attract big name free agents, cause they are both big market teams. The same goes for the Knicks and the Nets. Obviously, the Knicks have Dolan, so it's as if he throws their competive advantage out the window.

Also, this in nothing compared to the advantage the Heat, the Magic, the Grizzlies, the Rockets, the Mavs and the Spurs have cause there is on state individual income tax in Florida, Tennessee* and Texas respectively.
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All things considered, the Heat might have an even bigger competitive advantage compared to the LA and NY teams. I mean, Miami is massively popular as well, plus they are based in a state with no state income tax. No wonder LeBron chose to move there in 2010.
*Fwiw, Tennessee has a "Hall income tax", levied at a rate of 3% on income received from stocks and bonds not taxed ad valorem as of 2019. The tax is 2% as of 2020, 1% as of 2021, and fully repealed as of 2022.