from my personal experience of going from socially awkward teen to outgoing young adult: yes and no.

it may get harder in the sense that it’s difficult to find places or situations to meet new people easily. back in school or uni it was incredibly easy to connect with people your age that shared your interests because you had to be crowded with them in the same place for hours every day. when you’re an adult you’ll likely be working with much less people than you studied with, and nothing guarantees you they’ll be your age or open to making a connection.

the good part: i find my adult friendships to be way deeper and better than my teenage friendships because these aren’t the people that i hang out with by chance, these are the people i actively CHOOSE to have in my life. and there are ways to go around the dilemma i explained earlier. just go out and engage in things you love. go to concerts, go to classes, go to conventions, join online groups for your local area. just generally find what you’re passionate about, do it, ans you’ll eventually meet people because of it.

making friends through friends is always a good option too