Is following girls on instagram a big deal?

i’ve heard mixed reviews about this. some people say yes and some say no. my boyfriend follows and likes girls bikini and butt pictures. he hasn’t had instagram for two years then he got it back. he then he followed a girl that he knew in highschool that he liked all her pictures and that drove me crazy. he says he followed her because he wanted to no matter what i’ll always be bitching and complaining about it. I don't know if i should let it bother me or not. my mom and anger both say that i shouldn’t let it bother me because it’s just social media and he more than. likely won’t have a chance with them. but he’s DMed this girl before telling her how pretty she is so i feel like he can get her if he wanted to. I don't know im really insecure.
Is following girls on instagram a big deal?
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