oh hey look, another chance to yell about rp meta, my favorite past-time-

basically, when people say the animanga community is declining, they don't mean that new sites aren't being made and new people aren't joining the community; they're instead more indicating a net loss in terms of the overall number of sites existing and the overall number of people in the community.

vaguely in defense of the other side, animanga is extremely decentralized and has been for a very long time, which means it's very easy for sites to exist in their own little bubbles; however, that being said, it is also important to note that forum-based rping as a whole is in the decline since it's a largely insular hobby by this point (case in point: most rp sites don't tend to try to actively recruit from outside the community anymore) + discord is far-and-away more popular these days thanks to the ~instant gratification~ factor, the lower barrier of entry for newer rpers, and the increased amount of "rp starter pack" genres + fandoms.

animanga itself is also fighting an uphill battle with it being a smaller community compared to rl (meaning small shrinkages have a larger impact), the landscape increasingly polarizing into very large sites that are ~staples of the community~ vs fairly small sites that struggle for activity, and the proboards vs jcink debate dividing the community even further. the increasing prevalence of 18+ sites doesn't help, per se, but it's still far less of a problem for animanga than real life and i personally think the lack of "rp starter pack" genres + fandoms and the much higher barrier of entry for forum-based rping are larger contributors to the lack of younger members than any 18+ rules discouraging them when they're most likely to end up sticking around.

personally, while i do see new sites opening, i also see that existing sites don't tend to last very long if they're not starting out with a decently sized core of members and/or are run by a big name in the community (and even then it's kind of hit or miss), and the overall selection of sites to join feels more lackluster compared to years ago, partially because i'm much more selective about the sites i join now (aka i've shifted to mostly look to fill xyz rp niche i already like vs randomly joining a site because the ad looked neat) but also because there's just not a whole lot of "healthy" turnover in the community (aka your selection is either massive sites that have been around forever or brand new sites that rarely tend to last more than a month or two before sputtering out and it's very rare to find very much in-between that). along similar lines, yeah, i do still meet people i've never met before as far as i'm aware of, but the vast majority of them have been doing this for years now and aren't exactly new to forum-based rping (which i don't mind entirely since uh it's pretty stressful trying to deal with a newbie rper but it's still not healthy for the overall community to not get new blood coming in).

tl;dr it's a macro vs micro situation where like. yeah, you're not wrong, there's new sites being made and new people coming into the community, but if you step back and look at the bigger picture, the overall number of sites is pretty stagnant with turnover being more on smaller sites with v short lifespans over a general occurrence and the vast majority of the overall community are people who are already part of it versus brand new blood from outside the niche.