It looked to me like Grand Thumbs viewers who actually know how the Hi Point operates had reached a consensus regarding why his most likely was malfunctioning; it seems the firing pin was likely broken or a lemon/out of spec. Hi Point’s firing pin also functions as the ejector, so that could explain his ejection issues. That particular video was not very insightful because he didn’t try to identify the issue or understand how the gun is designed or normally functions.

From what I’d gathered (online, not as an owner), the carbine and pistol’s firing pin operate the same in that regard.

https://www.hipointfirearmsforums.com/threads/extractor-firing-pin-confusion.275331/