Gawd...
Scrape flutter is more easily measured than the article maintains. That is why Ampex included a scrape flutter idler on their pro machines, starting with the 440 transport, way back in the 1960s. The idler reduces scrape flutter by 6db @ 10KHz. Says so right in the specs! So a big 'Sheesh' on that one...
And its not that hard to hear differences in bandwidth either, once you know what to look for. In a nutshell this article is not only out of date, but probably was when it was published. Stu Hageman was an advocate of wide bandwidth back in the 1950s... he designed the H/K stuff like the Citation 1 and Citation 2, which are some vintage pieces which easily keep up with modern units, once properly refurbished.
The big thing that's happened in the last 30-50 years is our understanding of how the ear/brain system works. New things are emerging all the time. Not that the audio industry is paying attention for the most part; until they do, its likely that a lot of debates we have seen over the same period will continue.
We're pretty good and have been for a while at the circuit design side of things. The problem has been we've been designing for the wrong goals (look good on paper rather than actually sounding good). Now I am not proposing subjectivism in case there's a knee-jerk regarding my last remark, what I am saying is the paper specs generally don't allow you to tell how something sounds. That means the paper specs are a really good example of the Emperor's New Clothes. What is needed is to understand how the ear works and design for that rather than that bit of paper (IOW, your eyes...). Whenever we get around to doing that, the resulting specs on paper will tell you instantly how that equipment sounds. Subjectivism and objectivism will meet happily because they will be the same thing.
But a bit of advice: don't hold your breath. Somehow the industry has to climb out of its shell and actually acknowledge some of the advances in the understanding of the human ear. Its ironic for sure.