IMO, the *real* reason for commercial licenses was the concept that commercial drivers are driving much larger vehicles that require special training/skills to operate safely on the roadways.
I'm pretty sure the real reason is to make more money from licensing people who are in turn making a profit from that license. The gov't could just issue a straight vehicle license and leave it up to the owner of a vehicle to get whatever training is required to operate it safely, but they don't because there's more money to be had from fees on commercial enterprises.
If Uber or Lyft drivers are getting paid to drive passengers around then they should have to follow the same rules as other commercial drivers. Maybe those rules should be changed. Maybe regulations on cab companies are unduly restrictive to limit competition and that should be fixed. But, I don't think a "cab" company that just happens to allow its passengers to find rides using the internet should get a pass on the rules that cab companies with proper dispatchers and fleets have to follow.
If the rules are useless or harmful, change the rules. Don't grant exemptions just because the internet is involved.