You might want to read a little closer and dig deeper on data next time.
MSU's pass defense in terms of efficiency and yards given up per completion is NOT the worst in the country. In fact, it's fairly average. #77 pass defense efficiency nationally, in fact. Better than Auburn, Rutgers, Indiana, Maryland, Ball State, etc.
Fun fact. MSU's opponents have thrown the ball 522 times. The most in America. By far. There are only a few teams that hit the 400 mark. Their opponents throw on them a TON -- but don't run on them much.
Western Kentucky's QB threw 64 times!!! Purdue's QB 54 times.
You're citing total yards and giving absolutely no context. Their "horrendous" schedule actually features the #3, #5, #31, #33, #38, #41, and #49 most efficient passing teams in the country. You know where we rank? #81.
If you've actually watched MSU, their pass defense gameplan is to give up the underneath and keep things in front. They'll provide that cushion, which teams have exploited. They have NOT given up the huge plays over the top -- until Ohio State, that is. And OSU features the best WR trio to probably ever play in the Big Ten, so that's not exactly a shock.
Also.......the last time we played an MSU team with a reeling secondary? 2018. And we couldn't do jack shit on them.
CJF is no JoePa.