There are some "hurdles" to these pro amps vs audiophile amps like the ATI.
Lab-wise, pro amps don't have the same great SNR or crosstalk numbers. Not debating actual sound quality at all. Just the lab SNR and crosstalk numbers that many audiophiles talk about.
Aesthetically, pro amps probably don't look very pretty to most people.
So if people are displaying towers with piano black gloss, they probably want something prettier for amps.
Feature-wise, pro amps don't have the typical 12V trigger that audiophile amps have.
So, as already mentioned, these are 2 different markets.
Will pro-amp companies try to cater to audiophiles by using sexier chassis, 12V, and getting sexier SNR/Crosstalk figures? That will be the day.