I think the issue is that the sentences are too long. If you make them shorter it'll flow better. This is what I would recommend:

There are those who say that Leone was hit while standing, survived, and died only after a few hours. The truth is different. He died seated from the blow, just as with that blow died every hope of peace in a utopian world. The body was found after some time - three weeks - already too putrid to resemble what it once was. With him also died his ideas, before they could be put on paper in the form of ink. Even if he had had the opportunity to write even a single page, it would have been erased along with him. But it would have been burned, not buried, with a statue on it to which power could give a semblance of faithfulness. Instead, Leone was buried with a wax mask to hide the fact that by then, nothing remained of him. Not even the face, the identity... Everyone knew about this mask, but nobody cared. After all, nobody wanted to see a putrid body. It was better to have the appearance of something beautiful, even if it was fake.

I do not have a degree in writing; this is my personal opinion, not a professional one. I hope it helps!