Hugo is so strange, I’ve worked on a shortcode and it just did not want to work.

{{- $matched := where $allSeries "Params.lostInterest" false -}}

It took me nearly an hour to find the issue! The culprit was the camelCase spelling of lostInterest. As soon as I changed it to all lower case it worked fine. But the big catch is that for simple rendering the value this works:

{{Params.lostInterest}}

But in the where statement it needs to be written like this: Params.lostinterest.