Back in the day,
@Crystal and I used to run what were considered "spin-off" forums from GameWinners. This was before YouTube, vloggers, streamers, Discord, and all of the other "newer" means of communication for the video gamer corner of the internet. There were sites like IGN, the monolithic corporate entities. Then, there were the more independent sites like GW that relied on ad revenue to sustain itself. After that, you had the sites like ours, fledgling communities that were self-funded with the purpose of being something "different". We succeeded in the GW community because we used the same forum software, much like how people use that chan script to mimic 4chan's format. Familiarity is what makes a forum, or any content for that matter, accessible to your audience. In Crystal and my case, our familiarity in format and personnel gave us a strong beginning. The problem then became sustaining traffic, which is easy to do with a core group of members, as you'll see here. However, after a while, there is a plateau you inevitably reach. You may catch a few new members here and there, as we do here, but, for the most part, you get your core group and core content and that's it.
When it comes to growth? That's something that's gonna vary by platform. A forum like GW back in the day was even subject to stagnation. There were several periods where activity waned and membership dropped, but, perseverance and the ability to adapt is where you focus your attention on the avoid that. For example, prior to me becoming an admin on the original GW, membership began to sink due to a borderline authoritarian reign of a former super moderator. Rules were put into place by that staff member, and ultimately, it turned the forum away from a community and into a pseudo-political shit show mixed with rebellion from the members. One of the first things my co-admins and I did after being promoted was begin to rework the rules and enforcement. We were already well engaged in the community as super moderators, so it was a relatively easy shift for the members. It wasn't a "holy shit, new sheriff's in town" moment at all, because we treated it as an opportunity to change course. Since we were more involved in the community than the owner, we knew what people wanted, we knew what people didn't like, and we were a part of the community. We weren't just a figure hidden away behind the curtain. Which, brings me to my next point.
Your current viewership base. Don't rely on what people from here have to say, you don't even have to heed what I'm saying. I'm just giving you my two cents as someone that has asked the same questions you've asked before. Engage with them. Find out what they want to see from you, find out what makes them tune in, and find out what separates you from the hundreds of thousands of other content creators doing the same thing you're doing. You'll be surprised at how willing people are to participate when they have a voice. For example, look in the questions and suggestions forum here. Everyone is open to suggest stuff for this place, and every suggestion is open to discussion between staff and every other member. It has been like that from day one. That's the kind of relationship you want to forge with your audience, because, at the end of the day, y'all are on the ride together.