It's fair for very long-term users with a fading interest in what Heyuri is centered around to eventually lose their youth passion and move on. It's like expecting a middle aged guy working 9-5 job to pull all-nighters for netoge like he did in middle school, getting old sux like that!
Take someone like 9-san, since he was around during SH era, if he was a 21yo college student creating OC at late night in expense of failing classes then; that would make such a person almost 30 today, with a job and perhaps even a wife to take care of
Old users aside, getting new users for an imageboard also gets harder by each passing day, you can see 4chan activity charts on plebs archives to see a decline.
I'm still optimistic. As long as jaded users ITT keep their negativity off other boards, we will have more young users joining in to have fun (according to a juvenile perspective)