NGsim
Rubbish. Because of small GA and Military experience availability European airlines have been doing just that with complete safety for some time. With the correct selection and flight training many European airlines put 250 + hours pilots into RHS of A320/B737.
BA and EasyJet. (Europe’s Jetstar) for example. After Type Rating and Base Training extensive route training, in my airline 50 sectors with Training Captain, they have been safe and productive pilots.
It just needs the airline resources to do it.