Conference championships don't matter. Not when the discussion on Saturday was centered on OSU/LSU losing but still making the playoff, just as a lower seed. That 13th data point doesn't matter when most of these teams are playing FCS teams during the season. So really ND is playing the same amount of FBS teams as anyone else. Until there is some sort of uniform scheduling policy (number of conference games, no FCS on the non-conference schedule, etc.) no one can complain about Notre Dame's independence. They play as good of a schedule as just about anyone in the country.
Also, no one is strong-arming ND into a conference, especially by expanding the playoff and especially the NCAA. ND will tell the NCAA to kick rocks. And expanded playoff only makes it easier for ND. As long as it's a four-team playoff, there will never be a stipulation that you must win your conference to be in. No conference will vote for that because it eliminates the ability to get two teams in. Now if ND goes 11-1/12-0 a few times and gets left out, that would change a lot. Just don't see the committee doing that.