The SEC was a HUGE beneficiary of the old BCS system and the new four-team playoff system took them down a quite a bit. You sure are drawing a lot of sweeping conclusions based on one year of the new playoff system. And Ohio State was fortunate to play the fifth or sixth best team Saban has had in his eight years at Alabama.
Ohio State had plenty of opportunities under the BCS system, as did all schools.
The big problem with the SEC is that being such a strong conference, they tend to knock each other out and the SEC winner ends up being physically spent by the end of the conference championships. That's why the SEC benefited from the old BCS: the conference winner only needed to win
one game to win it all, not two games like it is now.
It will be very interesting to see what happens a few seasons from now when all the big conferences (SEC, Big 12, Big 10, and Pac 12) have a lot of competitive teams.