While President Donald Trump and Republican congressional leaders are still crowing about their big, beautiful tax cuts, they’re no longer boasting as much that it made federal income taxes simple.

Their promise that most Americans could file their taxes on a postcard has fallen by the wayside. If anything, the tax code rewrite made things even more complicated and confusing.

Just ask the folks in California and other high-tax states waiting in line during Christmas week, rushing to prepay property taxes in hopes of preserving as much of their deductions as possible.

For some, this strategy might pay off.

The GOP tax overhaul limits the deductions for state and local income and property taxes to $10,000 total, starting next year. For instance, a household in the 25 percent tax bracket could save $750 by making a $3,000 payment before the end of the year.

But for others it won’t be worth the trouble.

Complicating matters further, the Internal Revenue Service issued an advisory saying prepaid taxes are deductible only if the property is both assessed and taxed in 2017. That means that if a local tax assessor hasn’t determined a home’s value for 2018, a homeowner can’t deduct property taxes paid in advance. But tax attorneys are arguing what an assessment must contain to qualify.

The new law specifically prohibits the prepayment of state and local income taxes to get around the limit on deductions, but didn’t say anything about property taxes.

Prepaying property taxes is only the highest profile of various financial moves that people are considering after the tax overhaul.

Experts predict that more professionals — doctors, lawyers and, yes, accountants — will turn themselves into “pass-through” businesses for tax purposes to cash in on the overhaul. Under the tax law, many owners will be able to shave 20 percent off their earnings before paying taxes.

It just shows again that this tax monstrosity fails the test of “reform.” It didn’t make the tax system fairer or simpler. Mostly, it’s a huge transfer of wealth to the superrich and to corporations that will be paid on the backs of future generations and could lead to cuts in Medicare and other safety net programs for the elderly and poor. And because it also repealed a key piece of the Affordable Care Act, it will likely raise insurance premiums.

Most Americans already know this and don’t support the law. It will become even less popular if taxpayers get deductions denied — or even audited — after filing their returns next year.