I don't think we're quite there yet societally for Internet voting. There's enough claims of rigged elections already.
It's fundamentally a trust problem: the way it is right now, any idiot can witness the counting process and be confident it was all done properly. You can't do that with a computer, you have to trust that the computer does what it claims to do. It would probably lead to the same issue as with mail ballots as well, it would likely favor the left and the right would do everything to discredit the validity of it.
I'm sure clever people have a neat cryptographic scheme that I would fully trust, but apart from potential UX problems, it doesn't solve that probably none of my family would trust it even if I explained it to them. And I would understand them, given big tech is constantly invading our privacy, I would be skeptical too.
Paper ballots are tangible, anyone can see that people only put one ballot in the box, that nobody messes with the box or peak into the box (votes are supposed to be anonymous). People can see that the sealed boxes are moved and opened up then counted. The ballot pusher is silly but it also shows the attention to details to ensure the confidentiality and prevent any doubt that anything fishy happened.