And I tend to agree with much of this due to the fact that, when comparing an R/C to a full sized plane, the weight of the full sized plane is generally going to give it less stability(especially with a low wing design) than an RC due to the higher wing loading and the shifting weight of the occupants and load, including fuel. A full sized plane is also affected by winds more than an R/C due to the larger side area. If you watch a plane flying toward or away from you closely, it won't be pointing the direction it's flying but, rather, it will be crabbing into the wind. This is something an R/C never has to contend with, other than during the final approach to the landing area.
That is not a misconception, other than the being difficult to fly. If you look at the control systems in any of the front line fighter planes used by the US military, you will find they are all routed through a flight control computer due the the aircraft being so unstable that they are almost impossible to fly without said computer. The Extras, Edges, Eagles, etc, that are commonly seen on the show circuit are all also built to be unstable so the planes can do all the stunts that "WOW" the crowds. No one wants to see a plane slow roll when they expect to see a snap roll. A more stable aircraft may perform a roll but the rolls won't be sharp or crisp due to inertia and weight.