The problem with the example is: Some has used less where you would have preferred fewer. You answer with an example, where fewer is used but only less is generally considered grammatical. (In other words, the replacement goes in the opposite direction.) But it is perfectly consistent to say that fewer is restricted to countable nouns while less can be used universally.
Consistent with how language works. Words have partial overlaps and “subset” relations all the time.
In the case of less and fewer, there isn’t even really a problem, because there are very few cases where using less when fewer would (also) be appropriate leads to confusion. (Otherwise the same distinction would surely also exist for more.)
I’m afraid, the only real “problem” is that for people who are accustomed to the distinction, using the “wrong” one gives a nails-on-chalkboard sensation.
