I think ShermanOaks's larger point is that "scheduling FCS teams" need not enter the discussion of perceived disadvantages. We need not do everything SEC teams do to be successful. I also cringe at the mere mention that not playing FCS teams is a disadvantage.
There are plenty of FBS teams that, if scheduled, would qualify as games that could "allow the team to build confidence." Practically any C-USA, MAC, or Sun Belt team would fit that bill. Granted, I don't think the lack of Notre Dame scheduling these types of teams has prohibited us from success, but that's another conversation.
Back to the original discussion, USC and UCLA have never scheduled FCS teams. I doubt that has been a reason for lack of recent success for the former. Furthermore, starting next year, the Big 10 is avoiding scheduling FCS teams.