[svnt]

In PR terms they are managing the Overton window. As a strategy it is sometimes called gradualism or incrementalism.

Five-year-olds do not use this technique, they do what they want when they want to with no regard for their public image, which is what you are stating NASA will do.

[actinium226]

I don't see why NASA would need to manage any "Overton window." NASA loses very little if they decide to send the astronauts back on SpaceX. At worst, and this is very possible, Boeing uses this as an excuse to just ax Starliner, and NASA would be left without a secondary crew vehicle, but they won't lose funding, and their image would probably only go up since they would have made a choice in the interest of safety.

Boeing, on the other hand, stands to suffer a lot of PR and financial damage should NASA make that decision. They have an interest in managing this window. They've been lobbying NASA and tweeted something about how confident they are in Starliner, but they appear to really be on the backfoot.

The whole point is that NASA isn't "letting people get used to the idea." It's really no skin off NASA's back if they send them home on Starliner.