How do people deal with old friends they’ve emotionally detached from?

Problem/Goal: I’ve noticed na I detach from people pretty easily, and I’m not really sure how I should handle old friends who still reach out kahit wala na talaga akong connection sa kanila.

Context: I have friends from HS/SHS na wala na talaga akong connection with ngayon. Wala naman akong galit or bad blood sa kanila, parang nawala lang talaga yung connection over time. Same thing happened in college. I’ve had different friend groups every few years, especially after choosing my major. Although, I still hang out and talk to some of my old college friends, so it’s not like I completely cut everyone off. Sometimes though, yung mga taong na-detach na talaga ako, sila pa rin yung nagre-reach out. I appreciate that they still remember me and want to catch up, pero honestly, I don’t feel the same closeness anymore. Minsan parang I’m only replying because we have history together.

Previous Attempts: I still reply and occasionally hang out with them kapag nagyaya, pero I don’t really make an effort to rebuild the friendship or bring back the old closeness. I usually just let the relationship exist casually. For people who are also like this, do you still try to maintain friendships kahit na wala na yung connection, or do you just let them naturally fade? And do you ever feel guilty about detaching from people who technically did nothing wrong?