Keep in mind, it's not Pete Prisco coming up with these odds, it's Vegas, and they arent in the business of losing money. Last season, 16 teams exceeded their Vegas win odds while 16 fell short of them, which is fairly typical.
Gambling on preseason odds feels like a sucker bet to me. If everything goes to plan, and everyone stays healthy and makes their expected jumps, while nobody regresses, then yeah, that 7.5 is laughably low.
How often does all that happen though? Even before seeing if the upgrades even work and the offense is able to stay clicking with a new QB, and a small-school rookie being the only notable personnel change to an OL that has been a straight liability for at least half a decade now, if two players from the group of JSN, Cross, Leo, EJ, and Spoon take a wrong step into the turf, take a hit awkwardly, or have someone accidentally roll up on them, fewer than 7.5 wins is absolutely a possibility. If it happens to Darnold, it's almost a certainty.
It's a very risky bet. Most of you probably aren't degenerates like me though, who get addicted to anything that's even a mild thrill.