all have an estimated net worth of $3MM to $5MM. Unless they're really bad at investing their annual $30MM in endorsements your claim is just flat wrong.
Clark just signed an 8 year, $28MM shoe deal. That works out to $4.5MM a year and the shoe deal is always the biggest chunk of their endorsement money.
$30MM is way exaggerated and so is the $500K NIL deal you are referring to I assume (certainly some rich Donor can offer $500K if they want, but it would be waaaaaay above market value).