Do we have a sense of how much activity the board has seen since the change?

The link you posted is flat defective for both vBulletin and for Discourse. Though it’s obviously trying to be a vBulletin link. I wonder if you transcribed it badly.

I just Googled for the exact same thing [1920’s style death ray straightdope] and the first hit was the lead post in the Discourse version of the site:

The second hit was an earlier thread of almost the same title, and was also the Discourse version:

The wiki for Edgar Cayce was Google’s next suggestion.