Maybe NASA still wants to get something for the money spent launching Crew 9 and get some science done, not just be a rescue mission. They don't want to cut that mission short.
So from a keep humans safe while still attempting to complete the Starliner mission as much as possible, to me this is the best solution. In fact, it's kind of bonus for Boeing to test the automated return that was not part of the original mission. </spinDocter>