I find that most people don't reach out to previous friends if they haven't been contacted in a while. For whatever reason, I don't have that internal programming. Whenever I remember, I will ping my friends or old coworkers going back 20+ years and go out for lunch, and it's always a great time. It's best to not have too much pride over it, life is too short in my opinion.

And I almost never get a no when I make the effort. One of the people I spend the most time with as an adult is one of my childhood friends who we just randomly went for beers once after not seeing in 15 years and now meet up every month or two since we still had the same chemistry as we did as kids