Arnold Palmer's existence was like a black hole absorbing the souls of every Arnold born for several decades. Too big of an effect on the meta for any other Arnolds to be viable for a long time. You have to wait a bit for the meta to adjust.
"But imaginary dog who is imagining voices in their head," I hear you all say at once. "What about Arnold Schwarzenegger?" Fills a different niche, as Schwarzenegger or his title The Governator is more fun to say than Arnold.