> With regular passwords via a browser, you can ensure the channel is encrypted via HTTPS.

I agree. But there is still the issue of forgotten passwords and the infamous password reset emails. How do secure them in the face of "opportunistic encryption with STARTTLS"?

> So, you're simultaneously suggesting that everyone use 'email links for login' and suggesting everyone use a single email provider?

As I said in another comment, I was specifically answering to a sentence starting with "If you use GMail with several accounts and POP3". My point being, if you are already using GMail, then just use your GMail address to avoid the delay in fetching other POP3 accounts.

But it's true that password login has the strong advantage over passwordless login to let you login instantly if you (or your password manager) remember your password.

> > most users don't use a password manager
> What's your basis for this? Every browser in use today has a password manager built in. People promoting these bullshit "not a password" alternatives always claim "average people" don't use password managers, but never present any evidence of that.

My basis for this is that, year after year, I keep reading publications showing that most users reuse the same password on multiple websites. Just search for "password reuse statistics" and you'll find a lot of evidence: https://www.google.com/search?q=password+reuse+statistics. "Average people" probably use the password manager built-in in their web browser, but it doesn't necessarily solve the main issue which is password reuse. Since you're asking for evidence, what evidence do you have to support your own claims?

> Firstly - the main security concern with emailed 'login' links isn't the transport at all - it's storage/accessibility via the mailbox.

I agree. My mistake to emphasize attacks on the transport when the biggest worry is the storage.

> The part people always ignore when suggesting emailed links as an alternative, is that if an attacker breaches your mailbox, they could conceivably use that to access your third party service that uses login links, and the victim would never know, because there is no password being reset, no killing of previous sessions.

This problem is not ignored. We can for example watch IP addresses used to connect, and notify the user connecting on the "usual" IP that we have detected another connection on a new/unseen IP. I'm not saying this is easy, but this is probably solvable.

Moreover, I notice that most non-technical users around me, when they are unable to connect because their password is refused, tend to think this is an error on their side, and just reset the password, without thinking they could have been hacked, which weakens your argument.

> My conclusion: password-less login is a thing that exists via public key cryptography: see ssh, TLS client certificates. Emailing links to people is nothing more than a fucking stupid idea, and frankly it's ridiculous that your "other issues to consider" makes literally zero mention of any security concerns.

A civilized discussion would be easier if you could avoid the words "fucking" and "ridiculous". You're claiming that passwordless login ignores important security concerns. I think that the human factor (forgotten passwords, password reuse, etc.) is big in the list of security concerns, and passwordless login can be an — imperfect — answer. That said, I agree that using public key cryptography in the vein of ssh would be a lot better than password and passwordless login combined.