I've subscribed to the beta experiments years ago, before the dark patterns started emerging and I was actually looking forward to any changes, and you're absolutely right, it is totally abandoned. The subreddit has just become a place for people to vent their frustrations and to be completely ignored by the admins.

Sometimes I like to imagine that I was the only one still using beta.reddit.com.

It was used during the redesign where they added thumbnails like 14 years ago, to allow people to see the new design before it got launched.

This was the birth of /r/beta

The subdomain is basically the same as old.reddit now, but I continued using the domain all this time for no reason.

The /r/beta subreddit was repurposed for beta testing, but has been abandoned for at least 8 years. I don’t know why they leave the subreddit active.

The subdomain I can only imagine was totally forgotten.