I recall hearing about Alovoa a year ago and while it sounds nice with no ads or paid features, being open source, and private data being encrypted I have to imagine the userbase is incredibly small relative to other services. Google Play lists it at over a thousand downloads but it's also available through F-Droid so that may not mean much. I have to imagine the userbase is mostly men which might prevent some users from joining or sticking around.
Either way (TL:DR) I'd be curious to see what your experiences are with open source dating apps or even apps designed around making friends.
Have you thought of frendica? I think it's kinda what you're looking for but it doesn't seem too popular. Have you used bumble for friends? I thought bumble was for dating, I'm not sure how that would work for friends.
Friendica didn't use activitypub until it was too late which might explain the lack of popularity.
Bumble for friends is a separate service from bumble.