Just imagine one day in the near future, a 150 hour CPL holder is in the right seat and (God forbid) the captain becomes incapacitated...
Suddenly, this guy/girl is in command of a 20T turbo prop with fifty passengers and two FA's on board, barrelling into Sydney in weather like we've had in the last few days. With all the decisions to be made, having never been in command of anything bigger than a light single.
Not a pretty picture