YOU don't understand the difference between a tax cut and the amount of tax refund someone gets or doesn't get.
For all but a small percentage of people, taxpayers paid less tax in 2018 on the same income for 2017. A combination of lowered tax rates across every tax bracket and an increase in the standard deduction, and for those who lost the dependent exemptions for their qualifying children, a doubling of the Child Tax Credit MORE than made up for it. People owed less in tax in 2018 on the same income in 2017.
The very few, percentagewise, who saw their tax bill go up, and it was not drastic because their tax rate still went down, live in high-tax states or have extremely large mortgages. The mortgage interest deduction was capped at $750k. Anyone with a mortgage bigger than that doesn't get the interest deduction on that portion. And the property tax/state income tax combined amount was capped at $10k. In the past, these FEW people had no limits and so their itemized deductions were more than the standard deduction. Because of the limits, their itemized deduction has to be more than the $24,000 standard deduction for married (up from $12,700) and $12,000 single (up from $6,350). Very few people were affected by it, and those that were live in states where property taxes and state income taxes are very high.
So these people, who are not poor to begin with, should be complaining about the high taxes their states impose instead of complaining about Trump.
People getting smaller refunds than they expected is a completely separate issue. All a tax refund is is you overpaying during the year. If your tax rate was cut by an average of 3%, and tax withholding rates were lowered correspondingly, then doesn't it make sense that you paid in less money during the year? Wouldn't there be less of an overpayment to get back?
A very small number of people owed money after the filed their returns, and that was because they didn't plan properly during the year. There are many sources of income that are not taxed like a paycheck is.