Might depend on the Judge. I have witnessed Judges ask "You understand what you are doing, this will never go away, etc". Genuine inquiry to make them comfortable that the defendant knows precisely what they are doing. But you are correct, there is also a scripted line of questioning.
I can confirm that at least some judges take it seriously. The judge I clerked for paid careful attention every time, looked for nonverbal hints that the defendant had reservations, asked follow-up questions and, in at least one case that I saw, adjourned so that the defendant has more time to think it over and discuss with his lawyer.