Mr. Horgy I feel this due to their needs to be a progression before one goes to 400 kph. With a great powerful aircraft comes great responsibility and one needs to have the 1000 hrs to turely understand the power. Plus for you it gives you a more credible CV, meaning more options, meaning more possibility for a PTR.
Now for Carbheatin's comments; most airlines you speak about are turbo-prop ops who most American pilots know hire low-houred skippers. Plus for all pilots the first year is difficult then it improves after that.