He can't function because he doesn't have an NFL arm, can't see the middle of the field behind the DLine for approximately 15 yards and doesn't make up for any of these shortcomings with an incredible football brain and / or athleticism.
People were making Brees comparisons. If you listened to Brees on commentary a) he's clearly doing basically zero film work these days (Romo used to clearly do loads) but b) even he was calling out clear pressures e.g. "They're simulating pressure here, so you probably have to get it out quickly".
He used to obliterate us because he knew what we were running. Young clearly has no clue what the opposition is doing.