Both were kind of unmotivated -- the 1983 catfight and the nuDYNASTY catfight a couple of years ago.
When the 2017 reboot (comic reboot, as they tend to do in recent decades) was announced, it was a foregone conclusion that, in some ways, it would be superior to the original (if only because it wouldn't have the Pollocks on staff to suffocate and ruin it, frame by frame, year by year).
That's a lot. And it was assumed it would have a splashier production, because most shows today do, almost effortlessly and without even having to think about it.
But we also predicted that the superior casting of the original couldn't be matched, and that the semi-serious tone of oldDYNASTY would be replaced with hack-ish casting (although nuFallon and Sam Joe were okay) and the reboot would be too fast-paced and facetious.
All of which panned out to be 100% true.
The reboot catfight was a standard issue 21st century catfight, pop song in the background, and it doesn't really matter what "motivated" it.
But the bigger disappointment was the 1983 catfight which
should have been motivated (i.e., Alexis taunting Krystle over losing another child, after Alexis killed her first one); it should have been a
grande diva battle royale in which Krystle's "you miserable bitch!" line should have resonated with a gravely gravitas which shook the heavens, genuinely terrifying Alexis (whose "empty-armed madonna" reference should have been likewise delivered far dirtier than Joan gave it).
Instead, the original DYNASTY's lilypond fight was just silly. Campy, disposable silliness. And a sign of things to come. It's reputation, much like the series itself, somewhat unconnected to the reality of what that series was actually delivering.