Behind Most Tax Deductions, There Are Entire Industries and Jobs
For example, look at the deduction for private planes for business purposes. You might say, yes, eliminate it because it only serves the top 1%. However, who actually builds and maintain private planes? Blue collar laborers do, and if you eliminate the deduction, you may decrease the demand for private planes which would throw those laborers out of a job.
Deductions for charities are another example. Charities employ a wide variety of workers, from medical researchers to art history majors to educators to home health care workers. Reduce and/or eliminate deductions threatens those jobs as well.
The Republicans are baiting us into a trap. They want to lower rates first, and then they try to appear as "serious budget hawks" by eliminating deductions. The trick here is that they know that eliminating or reducing deductions will bring political pressure from lobbying groups to retain the deductions.