There could be several reasons why your boyfriend doesn't mind if you meet your male friends:
Trust: Your boyfriend may have a strong sense of trust in you and your commitment to the relationship. He believes that you will maintain appropriate boundaries with your male friends and that you value the relationship enough not to jeopardize it.
Security: He might feel secure in himself and the relationship, understanding that spending time with male friends doesn't pose a threat to your bond.
Open-mindedness: Some people have a more open-minded and accepting approach to relationships. They might not view friendships with the opposite sex as a cause for concern and understand that platonic relationships are entirely normal.
Respect for your autonomy: He respects your independence and trusts your judgment when it comes to maintaining friendships.
Lack of jealousy: Your boyfriend may not be the jealous type, which can be a positive trait in a relationship.
Communication: Perhaps you've had open and honest conversations about your friendships, and he's had the chance to express any concerns or insecurities.
Remember that every individual and relationship is unique, and there could be other factors specific to your situation that contribute to his attitude. If you ever have concerns or questions about your relationship, it's essential to communicate openly with your partner to understand each other's perspectives and feelings better.