Canada

Honestly, I imagine that wealth taxes would be difficult / cumbersome to actually implement in a fair way -- and they'd likely get significant challenges.

A more traditional approach, that I believe worked fairly well though I'm not totally sure, is to jack up inheritance taxes. Much easier to apply a tax on wealth during a wealth transfer, as all items get accounted for at the time anyhow.

Another approach that would likely dramatically shift things, would be to alter how stock market securities get used to secure loans: regulate banks to prevent them accepting securities at value. Doing that would turn off the 'tap' of money for many rich people, and instead force them to liquidate some capital to afford their high-service lifestyles. Ie. Cases like Musk, where you see the "richest man in the world" taking out loans using his stock as collateral in order to pay for stuff, shouldn't happen: make him actually sell his stock to raise liquidity.

so idk, i think there are options beyond just those two.