Since there are still several people on this site that don't believe in recruiting rankings, or that talent matters, I'll try to make it even more simple to understand.
247 has a yearly team talent composite dating back to 2015.
https://247sports.com/Season/2017-Football/CollegeTeamTalentComposite?Conference=Big-Ten
This gives a great idea of talent actually on the roster, rather than just looking at the last 4 years of recruiting class rankings. This only includes the rating of the players on the team for that year. It does not include players that left the program, were kicked off, etc, that may have bumped up the rankings for previous recruiting classes.
For the Gophers I factored in all games including non-conference and bowl games:
2015
vs more talented teams: 2-7
vs less talented teams: 4-0
2016
vs more talented teams: 3-4
vs less talented teams: 6-0
2017
vs more talented teams: 2-4
vs less talented teams: 3-1
Total record vs more talented: 7-15
Total record vs less talented: 13-1
Overall, the Gophers have a winning percentage of 32% vs teams with more talent, and 93% against teams with less talent.
Then I looked at only the B1G head to head including the B1G championship game. I didn't do non-conference and bowl games due to time, but I don't believe it would change the outcome much.
2015
Record was 39-18 in favor of more talented teams
2016
Record was 47-17 in favor of more talented teams
2017
Record is 36-13 in favor of more talented teams
Overall the record is 122-48 in favor of more talented teams, for a winning percentage of 72%.
So on average the team with more talent won't win every time, but they'll win 3/4 of the time. This is why recruiting/talent matters.