Ceddit was really good for r/askhistorians threads. You could read interesting takes on the questions that did not pass the mods snob filter.

It hasn't worked for some time.

There are alternatives, like reveddit. I think they all use the Pushshift API behinds the scenes.

That's correct. I'm the author of Reveddit. A few things like user pages and the desktop extension work entirely without Pushshift. Threads can function somewhat without it. I maintain a FAQ with details of how it works in case anyone's interested,

https://www.reveddit.com/about/faq/