It might be technically true. Most computers don't have modems because these days they are really only used for Fax/Voice services and other specialized services.

Most computers DO have network cards/Ethernet interfaces.

It would actually make a little more sense for election machines to use modems - the amount of data to be transferred is small, the machines could connect in a much more secure point-to-point manner allowing for fast transmission of results while limiting exposure. The connections could be encrypted with a one time pad which is about as bulletproof as encryption gets.

It would be a hell of a lot better than just plugging them into random internet connected networks. But even with modems it would only take one of those machines getting compromised, and one common vulnerability across the machines and you are back where we started.

So fuck that. I work in IT security. High security. And the more I see, the more the only thing I want counting ballots are triple redundant homo sapiens.