The California wealth tax is one step closer to becoming reality. The proposed tax measure, which would require billionaires to pay a one-time tax equal to 5% of their net worth, will appear on the ballot in November after opponents, including Gov. Gavin Newsom , failed to cut a deal with the union behind it before the June 25 deadline. Now the 200-plus billionaires in California — which has more of them than any other state and most countries — are facing the reality that the tax could become