Communities stay active as long as they receive votes. Over time, since their implementation, I've seen those that received votes grow in users and activity. Some have their golden age, but when they stop receiving many votes, users move to another trendy community where voting is common.
That's why many users don't even have a defined niche. In my country, there's a saying: "Stick to what you know." That's why I've never posted anything about crafts; I'm not good at it, it's not my specialty, and I don't even like it.
There are users who don't care; they just want the vote of the most popular community. So, if an art community is the one that receives a lot of votes, they start creating art, even if they have no talent or know anything about it. For example, years ago, a makeup community was very popular. I saw users who didn't even know much about the subject, but just to get votes, they would paint their bodies and put on makeup without having a clue what they were doing.
This leads to communities with many users, but very few are truly experts in that niche, and when the votes run out, they abandon it forever, leaving behind dead communities.
I've never posted anything about makeup, crafts, or video games because I'm not good at them; not without my niches. Although I was a photographer for years, now that I don't have professional equipment, it has prevented me from posting about photography. That community was also very popular for a long time, but even when it was highly voted for, I didn't dare post there.
The rules are another issue. I understand that every community must have rules, but some are truly absurd. There are communities where I've never posted or commented because they have rules that prohibit comments in any language other than English. It's completely ridiculous, especially in an ecosystem with a high percentage of Spanish-speaking users. If I know that the person who wrote the post speaks Spanish, why should they prohibit me from commenting in my native language? The administrator or moderator can overcome their laziness and use the browser's built-in translator to translate it. It's simple.
Furthermore, I am celebrating my ninth year here, since the Steemit days, and users always flock to post (even if they don't master the subject) in communities where they see that they receive votes.
You wrote a very thoughtful and insightful response, @jcrodriguez. I agree with you and find it sad that the Hive community has suffered.
All the points you raised are very interesting (and through-provoking), and if they were properly discussed... I think some things around here could change.
The thing is, despite the positive changes over the years, there are still "deep-rooted" problems that seem to be chronic (and I honestly don't know if they will all ever be solved).
At the end of the day, it is sad (and worrying) to think that it all comes down to who has the most power and what they are going to do with it around here.