that's not really true. and there is a rub
2022 - KC with Mahomes, he is not on rookie contract.
2021- Rams with Stafford, a 12 year veteran
2020- Tamp with Brady, a 20 year veteran
2019 - KC with Mahomes on Rookie contract
2018- New England - with Brady
2017- Philly with a veteran back up
2016 - New england with brady
2015 - Denver with Manning
so the winning teams have had veteran QB, except one, but that's Mahomes a generational talent. doesn't fall off a tree often. same with Brady, a generational talent.
but participants
2022 - Philly with Hurts on Rookie Contract
2021- Cinci with Burrows on a rooke contract
2020- KC with Mahomes not rookie contract
2019 - SF with Grapolo, not on rookie contract
2018- Rams with - with Goff on rookie contract
2017- NE with brady
2016 - Atlanta with Ryan not on rookie contract
2015 - Carolina with Newton not on rookie contract
so only past two year there has been two QBs on rookie contract, but going back 7 years, its less than half.
now, do we want to claim victory and say the past two year and that's a trend. we will see.
and with that said, the key thing above is that you have a heck of a better chance of winning with an elite QBs. and there is only about 2, or 3 at most in the league. subsequently, more QBs fail than succeed. its a bit of a gamble to go QB shopping every few years, that's why teams tend to hold on to their good QBs. as evident, then you have to be able to build a good team around them and provide strong support to have a chance, ala philly, SF, Rams, Atlanta, etc.