And surely taking action against parties who exploit that fact is their solution.

How does an security PoC and API library fall under the DMCA? See this comment: https://news.ycombinator.com/item?id=7273662

From what I recall, the DMCA is about copyright and trademark infringement.

The DMCA is also about "anti-circumvention". It makes it illegal to remove DRM that protects copyrighted content, or to create tools that do so.

That said, this takedown looks pretty bogus to my (untrained) eye.