I was heavily involved with the local soccer community, and as a coach/referee I carried my own detector that I paid less for a ready to go version than this DIY shield. I was not going to depend on someone else's gear functioning when these were so cheap.
Got a link to that detector? The cheapest self-contained lightning sensor in a portable form factor I know of nowadays is the Acurite 02020 and it's around ~$50 nowadays.
That's interesting. That's the same one I have, but I only paid $27.99 for it. I couldn't remember what the model was, but Amazon shows that I purchased that model and clicking the View Order link it shows $27.99. I guess I bought at the right time??? Maybe it's tariffed to death?
https://camelcamelcamel.com/product/B00EO1H3X8
Looks like it's steadily increased, labor maybe? Just a WAG on my part to be sure, I'm too far away to legitimately speculate.
likely the chip in it is out of production
lots of products like this are increasing because nobody is running the older cheaper fabs