Not very common on newer cars as it's all electronically measured.
Most current vehicles have 4 wheel speed sensors. For ABS, traction control, or other purposes. Most German stuff going back 20 years has used multiple wheel speed sensors.
Speedometers have not been cable driven in a long time.
I would be at least mildly suspicious if I went to look at a newer car where the speedometer was funky... Usually more than one thing has to have gone wrong to get to that point.
Either way, it should be fixed immediately. I'm not sure you could pass any inspection without a functional speedometer