For the pyramids specifically: their architects and builders were skilled artisans who got to own their craft from top to bottom. As such, they were well-paid and pretty respected. Very much not alienated, under Marx's definition.

I don't think Marx said that worker alienation was specific to capitalism, rather, his work was in describing the economic system of his time, and what that would entail for people living in it.

> It actually results from civilization.

I disagree, I can't think of anyone in Medieval Europe as alienated from their work as a modern sweatshop worker. Not that serfs had it better, but you get me.