Fields continues to be a player whose contributions are overrated by raw stats. He's like a 1970s slugger who puts up HRs and RBIs with a .280 obp.
He can pop off enough runs and bombs to get his yardage up, but he's so unreliable in must-pass situations that his team will struggle to convert those yards into points and points into wins.
His passing success rate (getting at least 40% of yards to gain on first down, 60% on second down or 100% on 3rd/4th) is 40.8%, 28th out of 34 qualified QBs. (Bagent is 4th at 52%).
His statistics take an absolute nosedive in 4th quarters, especially in non-blowouts, when teams know you have to pass.
He's also uncannily good at doing bad things that don't count against his passing stats. Hop around for 7 seconds on 3rd and 7 before finally eating a sack and hurting your thumb doesn't help the team win, but it protects your completion percentage and doesn't subtract from your passing yardage. Handing off a zone read when you should have kept or not checking out of an outside left run when there's two looming left side blitzers doesn't hurt your passing stats at all.
Wins are not a QB stat, but Justin Fields' historic run of losing isn't a coincidence or bad luck. It is directly tied to his extremely poor execution of his job at the most important position on the field.