@martinman , I typed two responses, but when they posted, they both came out blank so I deleted them. Maybe a browser issue.
The $99 DAC obviously lacks electrical isolation that will ensure the best performance in all systems, but the chip in that DAC is the result of decades of integration, and modern semiconductor processes and advancements in how to make a DAC. The advancements are not as dramatic as digital semiconductors over 30 years, but they are substantial hence why a $99 high performing DAC is possible. The chip does not require $1000's of supporting components around it to extract near its best performance assuming fidelity to the original analog signal is your goal. If you want instead art, that is going to cost you big bucks, and like any art, you may like it or you may not.