You could ask that question of every MPL cadet or 200hr CPL/IR pilot currently flogging around Europe in one RYRs 738s or EZYs 319s. I can think of a few "stall" related incidents (Air France 447, Turkish at AMS, Thomson at Bournemouth, Asiana at SFO) - all of them involved a loss of speed & system awareness/SA and none of them involved "cadets". In fact, pretty much everyone involved had thousands of hours. Draw from that what you will.
It is true the "cadets" will have fewer actual flying hours than everyone else when they hit the line but you manage this through training and supervision - especially on an operation where actual hands-on is, on the whole, limited to final stages of flight. It's not insurmountable; recruit good people and train them well.