Someone sufficiently wealthy can push off taxes until they die and their heirs can use the step up basis[1] to avoid them entirely.
There's also a huge advantage in the ability to choose when one wants to pay taxes even if they eventually do get paid. Buffet loves to talk about unrealized gains as a loan from Uncle Sam at zero percent interest.
- credit card: nothing
- mortgage: the house
- car loan: the car
One could make rules about loans secured by assets with unrealized gains (with an exemption for a primary residence).
PS Credit card reward points are taxed as interest income in the US so look for a 1099 INT.