Rising interest rates make debts worse and asset values (including those belonging to the rich) to decrease, whereas it's mostly just the value of money which improves.

Also, who is rich/poor and has assets/debts can be hard to tell from appearances alone. Would you call this guy poor [0]? Seems like he has a good life. Which begs the question... when we talk about taxing the rich, who are we thinking of exactly? Someone living beyond their means, or below their means?

[0] - https://www.youtube.com/watch?v=r0HX4a5P8eE