Being actively involved in the DAC industry over the years, I know of very few who are as passionate and innovative as Professor Nugent. There are some manufacturers who I am somewhat surprised they are as popular as they are or command the fees that they do. My conclusion is that manufacturers are more into profit since the internals are only mass produced generic parts, not necessarily of the best quality and not necessarily the best implementation or quality workmanship. Yet, the audio community speaks accolades for these units.
Second, there are those who simply are unable to achieve what Steve has done. So cost and implementation are why this is not often seen. This trend is a major part of the reason DACs devalue to 1/5 their initial MSRP in 2-3 years. Empirical gear used still hold better value than most gear out there.
Empirical is not the only digital manufacturing company that commands my respect, but Steve certainly has earned it. Three reasons: First he is passionately driven to innovate and brings items to market when they are proven reliable and beneficial. He also is able to see weaknesses in delivery of optimal signals and creates items that are versatile, bringing benefit to any component we choose to use. Having seen his internal work, most of which is done by hand, there are few today with this ability.