Personally, I would consider someone to be active if they log in/post a few times a week. But then if they don’t log in for a month, should they be considered inactive? I’m not sure how each instance measures this, and I’m sure it varies from instance to instance.
My adblocker keeps tabs of how many trackers it blocked and Reddit was always the highest culprit of trackers. This doesn’t surprise me, but I do not have/use facebook,snapchat,tiktok or instagram to compare it to.