Right, I understand the problem. Find and xargs can do wonders. However, that's usually an edge case (in my professional experience). I'm certainly not proclaiming the advanced-ness of 'ls' in this circumstance.
However, in the example in the article, he was using "ls" piped to "grep" in order to find all files with a 5 in the name. That would suffer from the same consequences you mentioned, on such systems, and is inefficient and verbose.
Note, I agree with your advice to teach "find" (and "xargs") to users.