Seems clear cut to me, what these people want
Well, what if the company have their own tie up with a TRTO and they get a cut for supplying the clients? Won't be so keen on your type rating then.
What if they fly a type you don't have? Not going to be quite as keen then.
What if it's a turbo-prop outfit and you have a jet type rating with no hours on type? Won't be so keen on your type rating then either, or the prospect of you hanging around long enough to make it worthwhile taking you on.
What if they prefer all their pilots to have gone through their own TR training? Negates much of the (perceived) advantage of having the type rating.
What if you don't get a job with your type rating and just under 12 months has passed and you get called for a sim ride? Still reckon you'd perform as well as a current-on-type pilot?
What happens if you still can't get a job?
PP
(just playing Devil's Advocate)
ps As for 'proving you can make the grade', plenty of pilots have failed line training........I know of a couple personally.