Yes, that's one example of it, the Eugenics wars was hinted to be the "Big" WW3 that killed 90 million and was the one that changed everything, then TNG upped the ante by creating a separate WW3 that killed 600 million.
So they mashed those two major wars into its history canon, and lot of times they even forgot what they did! That Voyager, Future's End episode was set in the mid 90's and there was no mention whatsoever of an Eugenics war. They couldn't keep up with it.
That's not counting the catastrophes like Khan shooting up Starfleet head quarters, then later in the same movie crashing a huge ship into Starfleet command.
I have to admit I had little to no reaction about Vulcan and Romulus being destroyed, and I should have. Before that, the Xindi attack on earth seemed more like a gimmick than a shocker. The main ones that did have an effect was what they did to Cardassia and the Dominion war itself.
If the shock value is getting lower, the new shows and movies are going to do damage to themselves if they keep showing disaster porn. No one might really care.
I had more reaction to Vulcan even though at least it exists in the Prime timeline though maybe Romulus will be saved in Kelvin and it sort of balance out in a twisted way.
I figure I'm just more familiar with Vulcan and had to watch Spock stand there helpless as it happened.