To me it's a simple case of affordability and perceived value.
The former is normally a function of your own financial circumstances and the cost of the ticket, the latter a more personal reflection on what is important to you.
Would I pay £2.5k for a CW return to the West coast of the USA? No. Would I pay £940 for a CW return to the West cost of the USA, starting in Dublin? Yes, and I just have.
There is a price point somewhere between £940 and £2.5k which for me, would mean the value I perceive does not justify the price paid.
The missus has a much lower price point - probably no more than £200 more than Economy per sector. I know other people who have a much higher price point.
One thing that I think is often overlooked, but is certainly important to me, is it isn't just about the time on the plane, or at the airport. If I have to do 10-hours in Y, I do not look forward to the flight [more dread it]. If I get to do it in CW, I actively look forward to it with a sense of excitement.
I'm therefore not just buying 10 hours in a better seat, with better food and better booze, I'm paying for the emotional benefits I get in the weeks before the trip too.