It is the stop that raises 4th amendment issues, not the requirement to produce a driver's license. A police officer may not hail you on the street and legally require you to produce your license. Or, for that matter, even to talk with him.
I don't personally agree with the DUI checkpoint policy given by the Supreme Court, but they have deemed such programs for "public safety" rather than "enforcement" which are directed at all drivers and not any one in particular to pass constitutional muster. I don't think so, but what I think doesn't matter.

