Most of us understand that depending who in is the game at any given time, determines what you (as a coach) can do or run (similar to what the reserves can/can't do in garbage time when they're on the floor). Any coach worth his/her salt knows that. The difference in skill levels between the starters and the bench players vary from team to team.
On some teams, the difference is almost nil, allowing the coach to substitute freely. On other teams like UConn and Notre Dame, the chasm is a bit wider. I'm sure most fans noticed when Crystal picked up her 4th foul late in the game, Geno switched her off of Dillard. Similar to trying to protect a player with 2 fouls in the 1st half by going to a zone from a man to man if you really don't want (or can afford) to take that player out of the game at that time.
How much would the game have been impacted if Collier had been in serious foul trouble, and had to sit for the better part of a quarter? Who ended UConn's scoring drought in the 4th quarter?
When Coombs is in the game, she's not going to give you the same options on offense that Williams will when she's in the game. Coaches know their players and what they can (can't) do.
Geno knows what he is doing.
It's interesting that some folks still question his player management decisions after all these years.