Myth check
Minimal pairs are only for linguistics majors.
Buy/sell, mother/horse, and ask/hear are beginner emergencies, not graduate seminars.
Verdict
false
Why
A contrast pair is two real words that differ by one sound. You already meet them at stalls and in class.
Five minutes of forced choice beats twenty minutes of humming tones with no meaning attached.
You do not need every pair in the language. You need the ones that change money, family, and directions.
Better framing
Drill the pairs that appear in your decks this week, then reuse those words in a sentence.
Practice tip
Open Contrast pairs, do ten prompts, then say 我买这个 and 你卖水果吗？ back to back.