I'd argue Penn State is a 7-5 or 8-4 team at best in the SEC. They are 2-7 against SEC teams since 2010. The 2 wins were against bottom of the barrell Auburn teams. They do just enough to barely beat bad Big 10 teams and always lose to top 10 teams. Sure they will beat an overrated Iowa or Illinois team here and there. But they have a huge talent advantange over those teams and barely squeak by.B1G is top heavy. I do think their top teams are good but they often have a win or two that they wouldn't have with a more difficult schedule. Penn State, for example, is probably a 10-2 or 9-3 team in the SEC (unless they get Texas or Texas A&M's schedule lol).
Ohio State would be elite even in the SEC. The issue is the bottom of the B1G just isn't good. Teams like Minnesota, Indiana (traditionally), Illinois, Purdue, Maryland, Rutgers, and Northwestern just don't recruit on par with the elites. Iowa, Wisconsin, Michigan State, and Nebraska have made noise or have the potential to make noise but even they can rarely be on the same playing field, talent-wise, as Michigan and Ohio State.
The last time a B1G team not named Michigan or Ohio State won a national title was in the 1960s.
The 4 West Coasts teams probably add some depth to the B1G, but UCLA, USC, and Washington came into the B1G on a major down year with coaching/player attritions. Only Oregon was a sold team from that batch and has frankly stepped it up to be the Champion.
Against similar talent, they are terrible. For example, they were blown out by Ole Miss last bowl season. That's before Ole Miss went to the portal and spent all their money. James Franklin's offenses are usually terrible. They wouldn't keep up in the SEC against teams that can stop basic offenses. They would be like Oklahoma this year. I fully expect SMU to beat them.