I cannot tell you how often I have received comments from my former students…that went out into the work-world and write to me, “You know, when you read that passage from Marx on alienated labor, I confess it didn’t mean all that much to me. But now—now that I worked in the corporate world, for example—now I know what Marx is talking about. Because when he uses the term that work is external to me, and that I cannot identify with it, I cannot put myself in that process of work, that the product which I create is not part of me and I cannot feel myself as part of that product, now finally I feel that. And sometimes people will write to me a year after they’ve graduated, sometimes ten or twenty years…and as they write back to me their refrain is this: why is it I have spent so much of my life, so many of my hours engaged in an activity that I’ve come to hate, why should I feel the activity itself cannot be part of me
—Dennis Dalton. Power Over People: Classical and Modern Political Theory. Lecture Ten: Marx’s Critique of Capitalism and the Solution of Communism. The Teaching Company. 1998.
I can identify with this quote in that I believe I would despise life if I was anything other than a college professor. But I don't know why alienated labor is any different in a capitalism system compared to any other system. At least with capitalism you get to choose your profession, to some extent. I think this quote really applies to the reality of life. I'm sure many a Soviet comrades felt very dissatisfied with their jobs, as did many a peasant.
By the way, surveys show that the people unhappy with their jobs are those without autonomy and responsibility. I would think that a socialist system contains far less autonomy and responsibility.