Well, nevermind anything nefarious, life can throw unexpected things in the mix too. This Old Tony was similarly away for a while recently (now back) after a family member died. I imagine it only gets more difficult to return too, once people notice and maybe you see them asking in comments, on Reddit or HN, etc. 'where' you've gone, and start to feel some need to not only return but explain your absence.
I check occasionally for new videos, I enjoy them and hope there's more to come, but I don't need to know 'why', it's none of my business, and he doesn't owe me anything. (I'm not a Patreon supporter, that apparent change is a bit different of course, perhaps just a mistake as you said.)