I would say that "electronic voting" means that the ballot itself is digital rather than physical. So, scantrons are not electronic voting and voter registries/ID/etc. are not ballots in the first place.

I think the supposed risk to electronic voting machines is that there would need to be thousands of them, are distributed, somewhat unattended, and operated by people that don't know them.
The possibility of an exploit or misconfiguration increases, and the ability to compromise someone supervising one of the polling station increases.
If there is are centralised systems, fewer higher skilled people would be required to secure/monitor/run the system. It can also be airgapped.

While some of these risks are also applicable to in-person and mail-in voting, these systems have been around for ages, are not proprietary, and anyone can figure out "how it works" and can make sure "how it happened" matches.
As soon as you get into cryptographic vulnerabilities and security, 99.99% of people would be lost in the woods

The rest of the questions, I feel, are more systematic things.

Because what you vote is supposed to be anonymous....

If you ignore the anonymous part, then it's obviously not an issue.

Paper voting leaves a literal paper trail unlike electronic voting that's always a total black box in all countries that have tried it.

Manual in person voting is not easily scammed on a scale that can swing an election. The slow, inefficient, in person, physical process is a security feature.

I don't get what's wrong with paper ballots sent by mail. It's convenient and easy, with a paper trail for recounts. It's worked great in Washington for decades.

Manual in person voting is easily scammed, just look at voting in Russia.

Let me check. *looks through window* It's not the biggest source of voting fraud. Biggest source of voting fraud is Venedictov's box - Digital Electronic Voting.

Fuck this shit, everything should be 100% digital.

Sobyanin approves.

it absolutely is not easily scammed at all.

every single piece of paper is numbered and tracked. (tickets and stubbs, basically). all counting is done by multiple people and watched by anyone who wants. political parties are banned from voting premises.

even better: early voting, in person, up to a week or two before. no crowds.

errors happen about 1 in 1,000,000 with a maximum of a couple hundred, and are caught immediately.

there is no scamming. all of the USA's voting problems are self-created.