No, not at all.
The main and about the only mechanical concerns related to cold, but rideable temperatures is freehub lube getting sticky preventing the pawls from engaging, and any lube/moisture in the cable sheaths causing poor shifting and preventing brakes from disengaging.
Your bike is cold and lonely...bring it inside and pour it a drink!
I rode a carbon bike in 21° temps yesterday. Didn't hurt it at all. A plastic bike with a service life of 5 to 10 years spending time 'sitting' in the cold isn't going to damage anything. Condensation, on the other hand, is something to think about.
Carbon fiber was [is?] used extensively in the aerospace industry, e.g., the satellite radio antennas on the Voyager spacecraft were made of carbon fiber. Outer space temps are typically 2.7°K (-270.45°C or -454.81°F) so I'm pretty confident the guy's bike is okay.
I've been riding a CF bike through the winter for the past 9 years with no adverse effects...but I've only been riding on planet Earth, so not the most extreme temps.