The short answer is no. A newer RV may have more bells and whistles which often means more things that may break. A quarter of RV require a major repair within the first 2 years. An older RV has been that has been broken in may already have gone through major repairs which can be a good or bad thing.
The most common reason we are called is due to human error. This means people have done something to cause something to malfunction. There is not a single common issue. Keep in mind an RV has many different components from mechanical, electrical, plumbing etc... There are also RVers from all different backgrounds and RV experiences. Someone may call because their water is not flowing and not realizing they have to turn on their water pump. Someone may call because their refrigerator is not functioning and not realizing it may be operated by propane.
While most who subscribe to an RV help service are new RV owners, veteran RVers subscribe for the peace of mind that they can pick up the phone and speak to an experienced technician at anytime.