Affecting a(n electorally) significant number of paper votes requires the compromise of more people and leaves more evidence than for electronic votes. (In general, for the quality of voting generally seen in first world countries)

Can you do better in theory, yes. Have we seen any evidence that various US election bodies can do better through using electronic voting, no. The exact opposite in fact.

It's similar to passwords: writing down all your passwords in a notebook and keeping it in your desk draw is a bad idea. But it's usually significantly harder to break into millions of desk draws than to break any given site's security.