That one is questionable. One shotting enemies is boring to some of us. There is some content that gets broken by one shotting enemies. Yes, there are some things that require you to wear down an enemy slowly. If you do not, the quest breaks since the needed content was not played.
Some older content is better than older. Best example off the top of my head is Grim Batol. While not as hard as it was once upon a time, The Timewalking version has its appeal to it. I have literally seen mythic raid geared tanks rage quit because they think it is like current dungeons where you can pull multiple groups in one large clump. Then they die faster super fast because all those mobs buff themselves and the mob. The other tank like that who couldnt survive the bosses because he ignored their mechanics and then got to watch me and the dps warrior handle it without a wipe. I like the older dungeons because you have to actually think in them
Then take Grizzly Hills in WotLK, it may not have super high end graphics, but, between the visual ambience and music, it hits the exact feel they wanted. It really does feel like you are in foothills and mountains. And for the record, I grew up in a valley in Montana. I know what that feels like.
So, yes, old content can be superior to some people, or just something they want to do again.