In "Fahrenheit 451," what do you think Montag learns from reading the last page of the script?

Montag probably learns that the script is so blandly generic and meaningless that it could apply to anyone.  Millie is excited because she thinks that she has an actual part in the play and that the characters are truly waiting for her script lines alone.  In reality, the script shows that the lines that Millie speaks are bland enough that a million others could have the exact same script -and they probably do after having dutifully sent in their boxtops to get their scripts.  Also, the plot of the script is most likely one that is mindless as is most of what is on the shows that Millie watches.  Bradbury was trying to show how neutral and politically correct everything had become.  He wanted to show that entertainment was more important than enlightenment in the society of "Fahrenheit 451".