
That’s actually a control tactic. They use it to isolate you from female friends. If the same guy also worries about you having male friends, it can quickly turn into a situation where he has an attention monopoly on your time and a whole lot of control. Don’t date men who say this to you.
Also it shows that he’s a misogynist. If he thinks other girls suck and you’re better, he necessarily also thinks that he’s better than the vast majority of women. Which is straight up sexism. Don’t expect him to compartmentalize it. He will be sexist against you too. Just don’t with these guys. They’re not worth it.