What do you think about this parental decision?

today i called my friend to ask him if he could come over, he said no because he slept until 1 in the afternoon. He explained that his mom doesn’t allow him to go anywhere, nor have anyone come over to his house if he doesn’t wake up by 10 in the morning.

so why do you think his mom has this rule?
do you agree with her not letting him leave/have people come over? or do you disagree?
he’s 15 and its summer vacation for us