I agree, I'd actually much prefer 30 or 35 to 40-50, but our society isn't set up well for that. There are tons of employers who will pay you market rate for normal effort --- normal being defined as 40-50 hours/week of diligent work.

What you can do tho is put up with the 40-50 hours a week for a decade and then have the rest of your life to decide what you want to do with each hour of your day and not worry about how much society thinks you should dedicate to working.