You should have paid better attention while the legislation was being proposed by Reagan and debated in Congress

“The U.S. Congress passed the Tax Reform Act of 1986 (TRA) (Pub.L. 99–514, 100 Stat. 2085, enacted October 22, 1986) to simplify the income tax code, broaden the tax base and eliminate many tax shelters. Referred to as the second of the two “Reagan tax cuts” (the Kemp-Roth Tax Cut of 1981 being the first), the bill was also officially sponsored by Democrats, Richard Gephardt of Missouri in the House of Representatives and Bill Bradley of New Jersey in the Senate.

The Tax Reform Act of 1986 was given impetus by a detailed tax-simplification proposal from President Reagan’s Treasury Department, and was designed to be tax-revenue neutral because Reagan stated that he would veto any bill that was not. Revenue neutrality was targeted by decreasing individual income tax rates, eliminating $30 billion annually in loopholes, while increasing corporate taxes, capital gains taxes.”