I think it’s a good point that these taxes don’t apply to most people. Another reason they don’t apply is that most people save for retirement using retirement accounts.
But nothing in the article implies that these wealth taxes apply to most people. The argument is that a 1% wealth tax is equivalent to a 20% income tax because, under certain assumptions, the government gets the same amount of money.
Only in theory. In practice it’s not equivalent at all because once you reach a certain (very high) level of wealth, there’s the “buy, borrow, die” strategy that avoids realizing most of your capital gains. I’ve also heard of proposals to tax asset-backed loans above a certain threshold, which is aimed at the “borrow” part of the strategy. But the concern there is that the super wealthy may quickly find a different strategy for tax avoidance, so a blanket wealth tax should be harder to circumvent. But as with anything to do with the tax code, those with the best tax accountants and lawyers seldom end up losing.