Every time I think something will finally knock the CD off its audio gold-standard throne, someone comes along and sets me straight. Again. In a nutshell: the human ear imposes real, well-researched, concrete limits on what can and cannot be heard. These limits were known when the CD standard was designed, and said standard more than encompassed them. All later "improvements" can't do any better because the ear hasn't changed. That's the first part of the article. The second part is a (probably vain) attempt to hammer down all the usual fanboy arguments against these simple facts.
This was all done to death thirty years ago when the price of CD players descended to a level most audiophiles could afford, not coincidentally right around the time I got into the audiophile hobby. Being the impressionable youngster I was I took all of that science very seriously, bought the cheapest CD player seen up to that point ($189 Emerson single-disk in 1985), and never looked back. I dabbled a bit with SACD but set it aside when I realized I'd never see those disks in the bargain bin and I'm one of those old codgers who refuses to pay $20 for what used to cost $8.
With success comes means, and I now have the means to have a comparatively high-zoot hi-fi rig. What surprises me most is I can now hear the difference between a good engineer and a bad one. Some of my disks, a few of which I've owned for more than twenty-five years, sound genuinely marvelous. Others grate with clearly audible artifacts, compressed sound, and poor spectrum balance. But these represent choices, good and bad, of the people who made the music, not the people who made the playback gear. As the article notes, the only real improvements we'll hear are those created by careful engineers skilled in their craft.