> Is there a reason why it's any more evil than patents on machinery or other industrial processes?

This is way outside my area of expertise, but my understanding is the patent would only prevent others from monetizing the patented technology for x period of time.

That to me would be the key difference. In this case the claim is you can’t even grow the grapes in your own yard non-commercially.

Is it illegal to infringe on a software patent even if you’re not distributing or profiting from the software you wrote?