I don't think it's wrong to say Brees probably would have thrived in any era of NFL history or that Baugh, if teleported to 2019, would have had issues finding a role as a backup quarterback. But, like, we can't really test that and this is a TV show where people can learn about the history of the league so picking historical guys for the purposes of the show makes sense, even if I think this thread is underrating Brees quite a bit in an effort to make a point.
I'm shocked Favre made it over Starr for many reasons. (I would also put Rodgers above Favre, for what it's worth.) Young probably deserved it but the guys in the 8-14 range or so are all arguable and you had to drop some of them (Bradshaw, Young, Elway, Favre, Brees, Rodgers, etc. I'd probably take Young over Elway.