(though with somewhat updated drawings)
Those were concept art renders of the design we got, not very fare off from the final version. Those exact renders are in the booklet that come with the Eaglemoss model.
The size measurements on that screen also do not work with that version of the design (or the final), because the DSC design is proportionally different compared to the TOS design.
Even if you were to scale the length down to TOS numbers, the other measurements wouldn't line up.
Although that has itself become problematic since it completely disregards the Starfleet design lineage and aesthetic laid down in Disco in order to trip over itself at being a faithful update to TOS.
I don't agree with this. Look at the Mid-24th century+, Starfleet design aesthetic was hardly consistent, no reason to expect the TOS era to be the same. We only saw, what? 2 different starfleet starship designs in TOS/TAS? 3 if you want to count the Bonaventure.
Look at the Connie Refit/Miranda to the Excelsior, and then to the Ambssador, they went from having no big glowy bussards to having them again. The Galaxy-Class shrunk them down, but they were rounded and bulb like.
The post-Galaxy Class, bussards became integrated right into the nacelles (though still being glowy) with a lot of ships (Sovereign, Prometheus, Intrepid), though some kept the bulb style, like the Steamrunner, Norway and Defiant.
Plus we don't know when the other DSC ships we saw launched. Remember the Enterprise is 10 years old when DSC Starts, and we don't know how old the class itself is.
The DSC Ships could be from after that design aesthetic. A mid way between the Connie style and the TMP era style.
Maybe the evolution wasn't great enough like the TMP era for them to refit the connie with the new nacelles, or the ship was still 'new' enough that it didn't need to be refit.