It’s a bit deceiving, as most of the large deep Blue States have party registration (particularly CA, NY, MA, NJ, MD - which accounts for 9.5M of the 12M difference), while most of the Red States do not (particularly Texas). Other red states, particularly in the South, have lots of people who used to vote Democrat, but now vote Republican...but never bothered to change their registration.
So I wouldn’t put much stock in these numbers - more like just another attempt to demoralize Republicans.
Well if they included the mostly republican states in this then the difference wold be different, but last I checked we had 5 states, not that I would expect a liberal to understand basic geography, and by a couple of the comments on here I see some did not even notice that not all states were included.