No, not at all! As you grow older, it may not be as automatic as when you are in school. Many of the people that you interact with might be focused on their own stuff (work, partner, family, hobbies, finance) and not too motivated to expand or even have a "social life" in whatever free time they have (if they even do). But this is not everyone. There is still a lot of people at every age that do want a social life, you just need to put in a bit of effort to connect with them.

And, a tip, do not consider failed attempts at socializing as a "failure" on your side. Perceived rejection often boils down to people being very attached to their free time, and socializing not being on their list of priorities. If you keep this in mind then you do not need to feel discomfort from rejection, and you can be active in your search for like-minded people without worry.