I guess it depends how you interpret Harvard’s “recommendation” of four years, just like they “recommend” four years of English and four years of Math, and
An ideal four-year preparatory program includes …four years of one foreign language.
with the caveat “you may encounter unique circumstances, such as resource limitations”.
I interpret it similar to how they previously “recommended” Subject Tests. (See the now-defunct “Subject Tests aren’t truly optional” thread.)
Also note that they specific “one foreign language” and “a single foreign language”.
Similarly, Princeton
we expect students will complete the following courses before beginning study at Princeton: …
Four years of one foreign language