Looking at the Big Ten, which is finally getting rid of the divisions next year so this won’t happen anymore, the committee likely believes osu already played in the conference championship last week. They lost. Those were the top two teams in the division. No one from the big ten west is close. They only have a team in the conference championship because it’s required. It’s like that every year because the divisions are lopsided. Starting next year it will be the top 2 seeds and theoretically Ohio state and Michigan could play two weeks in a row.
Anyway, the committee typically only factors in conference championships if a team wins (not just makes it) and they need a tiebreaker. Otherwise they look at entire body of work. Obviously, playing in that game and winning in really impressive fashion can also propel a team in (like Ohio state getting in over TCU 2014 when the Big 12 did not yet have a conference championship game). So team sitting at home not always rewarded.