The output of that code is *still* not nice, even today. Try it and you'll see.
I ran that code in multiple versions of Perl that I had handy. The output was the intuitive ("nice") version, even when I ran the code with twice as many iterations.
Note that your stance would produce 16 digits of noise for even trivial cases like print 0.1+0.2.
Yes, there is no one obvious best value for how many digits to show by default. C says 6, for example. So, you give a "slippery slope" argument, dodge one argument by concentrating on tangential aspects of the phrasing, and make a false assumption about whether I ran the code. Not much to refute here.