I, too, caught the oversight in the 10 cameras video, but we're being too harsh on the Northrups, folks.
The following link gets you to the Northrup's history of Pentax, where full credit for the first SLR is given to Pentax:
So, maybe it should be 11 cameras! Go to YouTube and search "Northrup Pentax" and you'll find lots of reviews. Tony is a fan of the K1.
One thing I like about the Northrups is that they're not in the industry's pocket. See Tony's review of the Nikon Z50 for evidence. Someone needs to tell it like it is. And ... great though the brand may be ... Pentax is waning in the market. Let's hope that K-New moves the needle in the other direction.