Yes, maybe even older. I trace it back to the addition of detergents in motor oil. Lots of folks claimed that an engine that used older non-detergent oil would get damaged by oils with detergents because it would break up deposits and send them circulating throughout the engine. While this has a little basis in fact, millions of cars switched over without a hitch. Somehow people have transplanted this argument over to synthetics which have detergents just like all other motor oils these days.