High income earners pay the lions share of all taxes so it is inevitable that anything that reduces taxes will disproportionately benefit higher income earners.

Put another way, if someone is only paying $20/year in total income taxes, the most you can possibly cut their taxes by is $20, or a 100% decrease.  If someone else is paying $10,000/year in taxes and you cut their taxes by $200 they benefited 10 times as much as the first person even though they only saw a 2% decrease in their taxes.

The notion that we can't have any programs that help reduce the tax burden just because those programs might benefit high income earners more is completely misguided and ignorant.