Reagan had a Repub controlled Senate for his fist 6 years. Reagan and the Repubs lost that leverage when they passed that amnesty/cheap labor dream like fantasy while the US citizen got screwed by a perpetual nightmare. In fact, the only leverage that was used was tax cuts but saddled with huge spending programs attached. Whoop-dee-doo, debt up to our eyeballs and the Federal government expanded rapidly too adding over 200,000 non-defense federal parasitic positions. Populists are just that, popular, unfortunately spend like crazy.
Plus Reagan never had a Republican majority House. However, he did have a conservative majority House for the first two years. That’s when things got done.