Trump wants a gas tax holiday. There's a much bigger problem looming

"What we generally think is that over long periods of time, most of the tax cut would go to consumers," he says. "But over shorter periods of time, suppliers — even though it's fairly competitive to sell gas — they still have some market power." And that market power means they could hike their prices a little bit, eating into those tax savings and keeping some of the benefit for themselves…

And second, waiving the gas tax can increase demand for gasoline; that's the natural result of lower prices. That could worsen the supply-demand imbalance that's driving prices up…

 https://www.npr.org/2026/05/28/nx-s1-5835634/gasoline-tax-holiday-trump-potholes