Paper ballots with physical marks are easy to track and recount. Digital paper trails are ephemeral. Whom does this benefit? The people counting the ballots.
The separate question, of why people are obsessed with it - implicitly in the United States - is a separate question.
sonofhans - to reply to your follow up here, I mostly agree with you. But I would soften it to say it is a tool that can be used for good or bad ends, and I felt the Swiss were using it more towards good ends. But I agreed that the ability to misuse it is intrinsic.
[1] https://www.news.admin.ch/en/newnsb/ZLw6w1GV_UdJKDocuT0sX
It’s not a United States issue. Look how Taiwan does vote counting: https://youtu.be/DUZa7qIGAdo. They don’t do it this way because of anything distinctive about American politics. Being self-evidently difficult to manipulate, without requiring voters to trust an opaque system, is an intrinsic benefit for voting systems.