The prolific posting alone couldn't be one person with other activities in their life like eating food or sleeping.

Over the course of 4 years, they've posted 5.6k times (comments and posts). That's less than 4 posts per day (5.6k/1500). Especially with posts like this, where it's just a link and a title, that's a totally reasonable time commitment. That's like an hour tops of posting, probably a lot less because, no offense yogthos, it's mostly not effort posts.