Yeah, I did a bit more digging on the 2011 patent.
It appears STI's patent on the double stack modular frame design expired so a few more companies now make the design but none of them officially call it a 2011 as far as I can see. I'm guessing the patent on the design is open but STI still own the copyright to the 2011 name.
Salient Arms for instance call it the 'SAI Red' which comes in 1911 and 'Hi Cap' versions, which I would guess coined or followed the Hi-capa term and the Airsoft world just slaps the 2011 name with it so that people know that they are not buying the 1911 version.
One thing I did notice with the Salient Arms version... They recently showed the pistol as the new service weapon for John Wick 3 and it clearly has 2011 stamped on the lower frame. Interesting. Perhaps they purchased a copyright licence?
Update: it appears SAI actually did purchase the 2011 copyright license, they use the term for the Red-H named pistol which I would presume is the version they licenced for the movie.