Not true in a practical sense.
In New Jersey for instance, while a “Real ID” is possible, and maybe is being issued for new Driver’s Licenses, replacing an older existing Driver’s License with a NJ “Real ID” version, requires an appointment. First you have to apply for the appointment, and then wait until your appointment date & time. I have applied and been waiting, for months, for an appointment date. Meanwhile I do have my passport.
I just got my driver’s license renewed.
I did _not_ have the correct documents.
They explained to me that they could renew the driver’s license (and did so) but if I wanted to fly without the real ID license I would need to bring a passport with me.
Since I have a passport that is not a problem.
So—there are a few loopholes....