I agree with you on your point. The only reason why this lady deserved to be pictured on Coulter tweet is if she stood there, knowingly taking a seat over Ann’s protests. If I was given a seat, and found out it was a stolen seat, I would not force out the passenger. That could be the reason why Ann posted her picture, the woman was complicit in stealing the seat.
I suspect that the more important reason that the picture of the woman was shown was to do an advance rebutting of a potential point that Delta could make that the move was done because of someone who was infirm, disabled or something like that.