That's not the impression I've gotten.
So there's two things being claimed here.
1 - Anyone saying someone should watch all the cutscenes is automatically a "hardcore player". That is false on so many levels. I can only speak for how I deal with this personally, but your claim is outright wrong.
I absolutely encourage people to watch the cutscenes and read the story of the MSQ as it plays out. But if someone just really does not like the story, or is just really not a story person, that's fine, too. I just ask that they don't criticize the story if they aren't going to read it.
2 - That it would take a "casual" several months to complete the MSQ. I have two answers to this. One, SO WHAT?! Two, if that's a big of a deal to someone, they will either play more, rush through parts of the MSQ, or do something else that speeds it up. This is not a race. You don't win a prize for finishing the MSQ in a shorter time.
You're attributing the lack of MSQ changes to people who had no impact on that. Sounds like you're just mad at this strawman you've created and named "Hardcore".
Another example is making Ultimate raids at all in the first place. Less than 1% of the community can enjoy this content. Yet they are constantly making new Ultimate raids while cutting more and more casual content. Do people notice the trend here? During ARR, there was only one level of hardcore raid - Coil, and there was also only one level of hardcore trial - Extreme. Then halfway through ARR they added Savage. In Heavensward they continued Savage and added PotD for hardcore 4-man content. In Stormblood they added Ultimate. Now they are adding Unreal. How many tiers of hardcore content do we have now? How many tiers of casual content do we have, on the other hand? And do you notice that casual content is the only content that gets cut, while they have only added hardcore content?
Translation: "Everyone who doesn't play as casually as I do is elitist hardcore!!" That's not how it works.