Reb Eliezer here are certain stats
In 2016 97% of US income taxes were paid by 50% of taxpayers.
The bottom 50% percent paid just 3%
Lets dig deeper
the share paid by the op 1% was greater then the bottom 90% combined!
So yes considering the fact that the wealthy are paying virtually all the taxes if you cut them they are going to benefit.
You know who else benefits?
The tens of thousands of US workers who then got bonuses explicitly tied to the tax cut.
The out of work workers who then had job opportunities as the economy finally took off after 8 years of being promised it would be “next year”
You see it’s the wealthy who create jobs and hire people, giving them more money gives them the capitol to do more of that.