They aren't autonomous robots. They are humans with agency who have chosen to take a different path that what they were taught growing up.

Of course, and you've completely failed as a parent if you've cultivated such a dysfunctional relationship with your children that instead of being able to confidently have an adult conversation with them about this you're biting your tongue and waiting for them to go away.

At 21 and 23 the ship has largely sailed, enjoy sleeping in that bed.