Did California lose Larry Page? The Google and Alphabet cofounder, who left day-to-day operations in 2019, has seen his net worth soar in the years since—from around $50 billion at the time of his departure to somewhere approximating $260 billion today. (Leaving his job clearly didn’t hurt his wallet.) Last year, a proposed ballot initiative in California threatened billionaires like Page with a one-time 5 percent wealth tax—prompting some of them to consider leaving the state before the end of the year, when the tax, if passed, would retroactively kick in. Page seems to have been one of those defectors; The Wall Street Journal reported that he recently spent more than $170 million on two homes in Miami. The article also indicated his cofounder Sergey Brin also might become a Florida man.

The Google guys, formerly California icons, are only two of approximately 250 billionaires subject to the plan. It’s not certain whether many of them have departed for Florida, Texas, New Zealand, or a space station. But it is clear that a lot of vocal billionaires and other super rich people are publicly losing their minds about the proposal, which will appear on the November ballot if it garners around 875,000 signatures. Hedge fund magnate Bill Ackman calls it “catastrophic.” Elon Musk, the world’s richest man, boasted that he already pays plenty of taxes, so much so that one year he claims his tax return broke the IRS computer.

Still, when considered as a percentage of income, even the big sums paid by some billionaires are way lower than the tax rates many teachers, accountants, and plumbers pay every year. If Musk, currently worth an estimated $716 billion, had to pay a 5 percent wealth tax, he’d probably manage to scrape by with a $680 billion nest...