If you remove the ability for people to spend money on worthless things, they will only have money to spend on useful things, and thus drive up inflation.
Not good, but better for society than rich people siting in a pile of cash forever? It is like vegetables. They are not good, but they are better than eating more carbs.
Cash is paper. No one cares about paper. Numbers in a bank account are numbers in a database somewhere. No one particularly cares about numbers in databases. What we care about is either investment or consumption, the use of resources. If rich people are not consuming their wealth then they are not using their resources. That means they’re available for everyone else to use because there’s only so much productive capacity in the economy and most of the time it’s almost all being used.
Investment is good for creating future wealth. Not using money rounds to investment, not at a personal level, but at a macroeconomic one.
Not true. Positional goods aren’t worthless but their worth is rank ordered, not “real”. Given that development in SF is de facto illegal there is going to be very little change in the number of penthouse luxury apartments. The prices can go up an enormous amount if rich people from outside want to move in.