Totally blanking on the exact quote and can't seem to find it right now, but there's a section in Capital where Marx explains that even if the workers get higher wages and living standards they're still getting exploited and it still sucks. We're definitely not richer than he could ever imagine, and he'd be surprised that we're still working 40 hour weeks.

EDIT: Not the exact passage I'm thinking of but here's a similar point he makes in his 1844 Manuscripts:

Even in the condition of society most favorable to the worker, the inevitable result for the worker is overwork and premature death, decline to a mere machine, a bond servant of capital, which piles up dangerously over and against him, more competition, and starvation or beggary for a section of the workers.

The raising of wages excites in the worker the capitalist’s mania to get rich, which he, however, can only satisfy by the sacrifice of his mind and body. The raising of wages presupposes and entails the accumulation of capital, and thus sets the product of labour against the worker as something ever more alien to him. Similarly, the division of labour renders him ever more one-sided and dependent, bringing with it the competition not only of men but also of machines.