Bingo!
There isn't a team in America outside of the NFL that can blanket cover OSU's WRs. It's going to be interesting to see who has some defensive success against them this year, and how they do it. It'll take a lot of mixing of zone coverages in the backend and NFL-level DL up front who can be disruptive without the need for blitzes. Even then, Fields would need to throw some picks, and the defense would have to be stout against the run. I haven't watched the other teams enough to know, but based on personnel alone, I would suspect that only Clemson, 'Bama, and possibly Georgia have the horses, depth, and coaching to pull it off, but I'd be shocked if they'd be able to do it with tight coverage on the OSU WRs.
Northwestern's WRs aren't at that level. Levi Falck and Kade Warner would be starting for Northwestern, too.