Someone with $2.5m to spend on end of life care is a heck of a lot wealthier than someone with $250k to spend on end of life care. No matter what, if everything else is equal, someone with $2.5m is very wealthy.

Arguments like "Ah, but they're not really wealthy because..." will always fail because there'll always be the case of someone in the same situation who doesn't have $2.5m, at which point the person with $2.5m is definitely wealthy.