If Harden opts in he’s gonna make $300M from basketball and he’s got a $200M contract with Adidas. $13M is chump change for him.
He's already made $220m. Who knows how much of that he still has, but if he didn't spend anything (which we know he didn't do) he'd only have $125m or so. Let's also assume he's not investing in index funds. He's probably investing in ****, some stupid, some good. We'll just say he's not making anything for the sake of simple math.
The remainder of his contract is $133m. Let's say he adds another 4 years at $200m. If it were in Texas, we're talking about $300m at this point, in take-home. But in NY, we're talking about just $265m.
It's going to be an extra $33m+ in taxes, and that's not counting how the Adidas stuff will be taxed, but I have no idea what living in NY does to that, if anything. Say he kept all of that. Now we're at about $365m.
He's a rich man and should live better than any of us can imagine but he should also notice that 10% of his wealth is gone. That's a huge chunk, especially if he wants to do ambitious things with his money. It's also a huge chunk if he's blowing all his money, which wouldn't totally surprise me.