I'm with you on that but I was surprised to find out during the last Brazilian election that they seem to do most of their voting on electronic machines and it seems well accepted over there. At least when I mentioned that to Brazilian colleagues they seemed fine with it.

This video (in Portuguese) shows a "tear down" endorsed by the manufacturer: https://www.youtube.com/watch?v=4wrMLzqgKEI

Both the tone of the video (unsurprisingly, given its "officially endorsed" nature) but also the comments seem overall pretty positive. Even though they mention that the software is closed source and you basically have to trust the manufacturer (and any third parties making hardware and software for the device along the way).