https://www.reddit.com/r/redditdev/comments/13wsiks/api_upda... and
https://www.reddit.com/r/modnews/comments/13wshdp/api_update...
Reddit really buried "no nsfw outside official reddit apps" (from the end of your first link). Didn't Tumblr do something similar and lose a significant fraction of its userbase and revenues?
I assume they hope to attract more advertising money this way.
There was a few months where it was required, but it isn't anymore.
I’ve been in tests where the entire site is gated, demanding I download the app. I’ve been in tests where SFW content is marked as NSFW, demanding I log in. Etc.
Everything else is secondary and most product managers don't view a/b tests as anything other than experiments on ways to increase those stats.