GPU mining is much more profitable.

A 1080 Ti makes more than an Antminer S9, D3, or L3 despite consuming a fraction of the power and producing none of the heat and noise. It also has kept almost 100% of its resale value, while the ASICs have lost almost all of theirs.

Ultimately, the only people who benefit from ASIC mining are the manufacturers of ASICs. They are effectively taking a big chunk out of the zero-sum game of cryptocurrency mining and giving nothing in return.