Somehow we manage to secure electronic banking despite possibly corrupt bank tellers having unmonitored access to the ATMs. I’m sure of the money were there we could secure voting the same way.
We also accept entirely different transparency for ATM transactions, can easily correct issues afterwards and given that it's about monetary damage, it can be insured. ATMs are regularly modified to steal information, and it is primarily fixed be insurance and chargeback mechanisms, the voting-equivalents of which are difficult.
It takes a long time to detect and fix problems. That's OK with ATM machines, because if you catch the insider who tampered with them months or years later, you can put them in jail and probably get most of the money back. But reversing election results more than a day or two after the first announcement is really bad for the stability of the country.
In fact, people are still digging into whether voting machine fraud happened in some states in the 2016 election. Any result now is too late.
Also, the nature of hacks is that you can often detect that one occurred, but not exactly what was changed. How would you take the news, "It looks like the Russians had root on every voting machine. But we've reconstructed the correct vote counts from analyzing deleted database files found in the free block list, and the winner is..." Not too convincing.
Electronic banking is defrauded on a regular basis, including at the endpoint using jackpot schemes and more. It’s acceptable for banking given the amounts stolen are ultimately trivial, but not for voting.
Sometimes they get detected and fixed, and sometimes they just get written off because they are small amounts.
Besides an important part of banks fixing issues like this (when they do fix them) is that someone (often the bank itself) must lose money, which they inevitably notice. In the case of an election, no one would ever know if their vote was stolen because they have no way of tracking it once they cast it. You seem to be blindly assuming that every problem will get detected and fixed which is mindbogglingly niave.
What happens when there are election irregularities detected after a winner has been declared?
2000 presidential election. Bush declared victor, but a Florida state law called for a recount as the margin was close. Recount was stopped, original election result stands. [1]
2016 brexit referendum. Leave campaign wins - and is later found to have broken campaign finance laws [2]. Original election result stands.
2016 presidential election. Trump declared victor, but evidence emerges of Russian interference [3]. Original election result stands.
There's no point in detecting irregularities after an election is over if they aren't going to be fixed - and history shows they won't be fixed. I'll stick with pencil-and-paper ballots thanks very much.