Why do the girls have almost all the unusual names, but the boys don’t have nearly as many unusuals as the girls?
Because there are approximately 6 times as many male names as female names in the TeNaCh.
Refoel is common, but why have I never met a Tzephaniah? considering we recite a Possuk from his Sepher immediately preceding Korbonos each & every morning. & why have I never met a Yishmoel? who was such a smart Rabbi to devise the 13 mnemonics to learn Torah? & why have I never met an Abbaye? nor a Robbo?