There are problems that electronic voting does solve: in some countries, moving paper ballots are problematic and subject to tampering. This shows up in mail-in voting, where there's always a risk of loss and delay. Overseas voters are an issue, e.g. deployed military.
There is a specific problem with mail-in voting and disabled voters, for example elderly people who can't go to the polls and can't get an electronic ballot marker. 25 US states deliver ballots electronically and 15 allow electronic voting for this specific case [1].
[1] https://www.ncsl.org/elections-and-campaigns/electronic-ball...
Registration of such voters can be audited and checked carefully to limit their numbers (since they must be inherently limited), and ballots can be delivered to them, or voting equipment can be brought to them (e.g., elderly care homes). I'm not sure much can be done to make voting by the permanently confined secure. For military the military itself can help a great deal. For civilians overseas, either come back to vote, vote at a consulate, or don't vote -- I don't think it's necessary to bend over backwards for civilians who choose to be overseas unless a country has a huge proportion of its population residing abroad.
Some countries solve that by just banning mail-in voting and moving paper ballots.
In France for example, voting happens on a specific day with transparent ballot boxes, with the counting happening in the polling station (you may stay for the whole day in your polling station if you want to oversee the whole process). Yes this is problematic for voters in foreign countries, because they need to go to the embassy to vote, but the voting protocols chose transparency over practicality.
IIRC, deployed military get a polling station in their military base. A voter may also designate someone in the same polling station as theirs to vote in their place.