Learning Spanish in school was the single biggest waste of time. 14% of the country are native Spanish speaker! Many professions require some spanish! Those were the arguments back then as well.

However... unless you account that the native speakers and heritage speakers will learn English, making your ability to say cerveza useless. If you aren't fluent and have professional Spanish qualities (like Medical Spanish), its useless. Learning Latin or Greek would have been more useful, at least I could struggle through Cicero in Latin, than saying 3 words in Spanish before the other guy switches to English.

If we find a way to make 4-6 years of language instruction reliably lead to a reasonable level of language competency, maybe. But until then, the student's underlying interest in the language is much more important than any abstract sense of usefulness. I took Spanish in highschool, and despite being moderately ambitious about it, never got very good, and never got much use out of it, despite living in Florida and Texas. I suspect (although alternate history is hard, so I can't guarantee) that I would have gotten a lot more out of Japanese, simply due to alignment of interest.

If you extend that logic to the world, is it malpractice to teach anything before Mandarin or Hindi?