It did work in terms of what the Reddit owners wanted, which was engagement - they did get more people onto their app and using their platform. The owners got just what they wanted.

In return, quality has fallen off a cliff. Moderation on some of the most popular subs is scarce, so all the popular ones have started to coalesce into a 'blob' of sameness. Discussions are poor as well, and misinformation is rife.

For the niche subreddits, often dedicated to one topic, where there isn't a lot of traffic, not that much has changed. There's still a decent amount of engagement. It might be that some quality has fallen off there, but it's the "new normal".