Flying clog,
Well then, perhaps you have indeed flown both jets and turboprops (so have I)...but suspect that you have never flown the earlier transport jet aircraft...they were a handful, not for the unwary.
When a company recruits for a particular type, they look for experienced guys, not amateurs (and no, not suggesting that turboprop guys are not qualified). IF they can get 'em, why should they look elsewhere?
Suspect you have not been 'round all that long, otherwise you would know better.
Wonder why the younger crowd always thinks that the cards are stacked against them?
Companies recruit based on need, not just because you need a job. IF the human resources department did not select the best qualified, based on their assessment, they would not be doing their job properly.
Simple as that.