Again, yes it will. Anytime you expand the numbers of teams playing for the championship, it lessens the impact of regular season games. To use a very simple example, in 1970 in the NFL, there were two conferences, 3 divisions per conference. The division winner and one wild card made it to the playoffs, that's it. Regular season games were much more critical then. Now, was the popularity there? No. Access to games was limited, obviously more difficult gamble and fantasy football wasn't around.
So from a college football standpoint, there are 4 going in this year's playoff, and as of today there is what, 6/7 teams with a legitimate claim to make the playoffs, and it's really down to about 5 teams.
Now, will the games be hyped and hyped, of course, the networks do have to "generate" interest and they do that well. But believe me, some of the early season college football games will be less important to many because most of the big boys will have a slush of 2-3 losses they can afford before it takes them out of the playoff.