It's strange for sure. I'm surprised I had never heard of it until about a month ago.
And I agree 100% with your "Barnum effect' kind of thinking. This is the part that surprised me:
"On August 24 and August 25, on Google Trends search for 'Shemitah' had a score of 100, meaning 10 percent or more of all the searches from that region was for this particular word. A Youtube video on the topic that was uploaded about two months ago and deals with an impending financial collapse, has already been seen 1.1 million times," the article reports.
Apparently more people know about it than I would have thought.
But I haven't even seen a single mention of it yet on the television.