*added note*: another reason is that both are almost the same thing as the basic idea is the same, with a few changes. They got a virtually similar rating, both have a similar plot, only differences are the ending, the actors, and lines and songs. And also the 60s one is in black and white, they have the 60s one in color but it’s paid. In conclusion while they have some differences, they are still almost the same movie, and should not be age restricted!