Despite being created 15 years ago, r/Bald has been a niche community until very recently. In 2019 their top post of all time only had 500 upvotes. Now the sub has multiple posts with over 100k upvotes and it’s at the top of the front page daily.

What changed? Nothing actually.

The core userbase of Reddit are millennial men. This was as true 15 years ago as it is now. Except 15 years ago this group would be made up of people in the 15-30 age bracket, while currently they are 30–45. Male hair loss really starts kicking in in the mid-to-late 30s, which means an average redditor started to bald recently. In turn, they all looked to reddit to find support, catapulting a tiny community to the top of reddit.

I know this isn’t some grand theory of reddit, but I found it interesting how such a random demographic detail can have a fairly big effect on the site.