A tax on luxury items of all classes that goes directly towards funding tax credits for low income families or some form of UBI
Example:
Automobiles above $X0000 are taxed an additional 10%
Houses above 2x the median house price in a city are taxed an additional 10%, or 15% above 3x, 20% above 4x etc
Restaurants charge an extra 10% tax when the bill is more than $XX per person
(I’m no economist and those numbers are by no means optimal)
This way, you can make $3000000 a year and still not get taxed more than your normal tax bracket unless you want to SPEND it on luxury items. If you choose to live frugally this tax doesn’t concern you.
The idea is that equity isn’t just about money. It’s about quality of life. Every time the mega rich splurges on fancy yachts and designer bags, some of that money should actually “trickle down”