It explains a lot if Discovery is the product of being legally obliged to be visually and tonally different from the original canon. The Enterprise was reportedly legally required to be redesigned. It feels more like a Kelvin universe tv series.Everything in that video is speculation and opinion, not fact.
Discovery is in the same timeline as TOS, they even used footage from “The Cage” in one episode.
CBS owns the rights to all of Star Trek, including the designs.