relying primarily on discord for most ooc interactions doesn't entirely explain why want ads are just not getting taken / i think some of it has to do with the want ads themselves / rping just. becoming a lot more insular now than it was even two or three years ago. people mostly rp within their friend groups now, and most of the time in my experience, the fact that a want ad exists at all means that no one was interested in the concept (or that they're not part of a friend group at all). i think a lot of people join sites with the thought of wanting to play out xyz former character they've had, and a lot of people just... don't check out the want ads anymore
^ I can definitely see this, but I also think it depends on the site and the community. KD is pretty dependent on want-ads (based on our theme) so for us it doesn't have to do with friend circles (we're also so small that I think pretty much everyone is friends with each other on KD); fortunately, our want-ads get regularly taken up by new members or seasoned members alike though some hang out on the backburner for a little while.
That being said, when I was perusing other sites I definitely noticed a different "culture" in regards to plotting, want-ads, and threading all together. It was pretty hard to get plots, some people would act like it was a chore or couldn't be bothered to pitch their own ideas and want-ads was like pulling teeth (I'm one of those people without a group of friends for every site I go to). I can't say/agree if it's becoming more common, but I definitely saw what you mentioned at the other sites I tried out. So, your theory might have some basis to it especially when compared to like... ten years ago. I don't think it was that much different three years ago.