It was an interesting video, but after watching it, I linked the Ralph Gilles videos and went down THAT hole for a few hours, ending with his hour on a 2019 "Autoline" segment. An interesting few hours!
As long as it took Chrysler to de-escalate their finned wonders, Cadillac still had evidence of their trade-mark fins on their 1967 models. With Thunderbird ending their fins with the 1963 models. Which brands were leading or following in this respect can depend upon how one looks at things going on back then, when everybody was seeking their own signature designs (or adaptations of others' designs).
By observation, many of the Chrysler designs looks poorly in some color/model combinations, but spectacular in others. IF the dealers had capitalized on those "spectacular" combinations, sales might have been different?
Just some thoughts,
CBODY67