When I talked to BYU AD Tom Holmoe about BYU rebuilding a schedule basically from scratch, he made this important point about conference affiliation. He's had to explain to his non-football athletes why they can't play. It's not at all because of their own behavior.
He said he understands why leagues make certain decisions based on circumstances that other members face. That is part of being a member of a conference.
Anyway, it's relevant to the Big Ten situation. Just because one team believes it is safe enough for it to play doesn't mean the entire league is in position to do so. Or the majority of members.