Taking the young pilots as co pilots, I do believe happen even on majors (at least that what I read on sveral forum with pilots as members). The problem is the captains usually already seasoned ones. Several major airlines from what I heard ussually put the young co-pilots with pilots that already have more than 20000 flight hours.

The pilot on this Lion plane, already have 10000 hours. However some Pilots in here say, its still not enough compared to say major airlines practise that put 15000 + hours before a co pilot can be a pilot. That’s not clear whether this pilot have 10000 hrs altogether, or 10000 hrs as pilot/captain.

Lion according some forum already improved the quality of the maintanance and support, and also they have planes with average age below 5 years. However the quality of pilots and the schedulling flight hrs which rumours say above average major airlines, that being put under scrutiny.