This whole thread with the separation of physical and mental work is depressing. Marx was right about one thing capitalism destroys craftsmanship and physical skill in the workplace.
In Marx's view, alienation is a symptom of the industrial age and of capitalism. A worker on a production line sees only the part of the work that he is involved with. He has no knowledge or control over the final product that is produced and sold. Man specifically the workman has no relationship with the goods that he is producing. He is alienated from his own labour. He works purely for the money. There is no satisfaction in the work that he does.
By contrast a craftsman such as a traditional shoe-maker is involved in every aspect of the production process. He may even make shoes for a specific individual. He will select the leather, measure the feet, and lovingly make the pair of shoes. He is proud of his work and enjoys handing over the finished goods to the new owner. Contrast that to the worker in a shoe factory. In all probability, he is involved in only one part of the production process. He rarely gets to see the whole shoe and never sees the people that buy the shoes. The skill or craftsmanship required to produce the shoes is almost gone