Here is a recent BLS study called "Characteristics of minimum wage workers" https://www.bls.gov/opub/reports/minimum-wage/2019/home.htm
"In 2019, 82.3 million workers age 16 and older in the United States were paid at hourly rates, representing 58.1 percent of all wage and salary workers. Among those paid by the hour, 392,000 workers earned exactly the prevailing federal minimum wage of $7.25 per hour. About 1.2 million had wages below the federal minimum. Together, these 1.6 million workers with wages at or below the federal minimum made up 1.9 percent of all hourly paid workers."
So I'd guess closer to 10% of people make the minimum wage in their jurisdiction (1.9% x 4 + I assume more people make min wage when it's higher)
Very interesting though that 3x as many people make below the min wage as actually earn the "minimum" wage.
More generally, I'd encourage you to question the mental model that made this sound like a potentially true claim in the first case. An economy where most people are paid minimum wage would be incredibly different than the one we actually have.
It is kind of fascinating that people have such wildly different ideas about what the objective facts are, and how that must flow downstream into their worldviews and politics. Between 51.6% and 2.3% is not a small difference! Those are very different worlds we could be living in!
[0] https://www.bls.gov/opub/reports/minimum-wage/2017/home.htm#....
So yeah.