Why do you think that? Public key authentication systems are invariably more secure, and a wide variety are also simpler for the end user to use.
It’s a misconception that they are in opposition to each other. Why would they be? One’s about knowing who’s doing something and the other is about how much effort it takes to do it.
Public key authentication is more secure than nothing, and is more convenient than shared secrets and symmetric encryption, but bit for bit the secret material necessary for public key cryptographic schemes to be secure is more data than is required for symmetric algorithms.
But more to your point, public key cryptography is basically a usability nightmare. In order to talk to anyone you need to first validate their key using an entirely out of band scheme you already trust, and if you don’t do that then all the end to end encryption in the world is theatre.
Of course I’m being hyperbolic, it’s the internet, but seriously there a lot of people feeling secure with public key systems that are either totally insecure, or could be insecure and they wouldn’t know, or are secure to some random bystander but insecure to people and organizations that are often included in people’s threat models.
Because in general, making things more difficult for an adverse party has great potential for also having side effects for proper users.
And conversely, making things easier for proper users very often also makes it easier for adversaries.
You’re right that it’s not a strict 100% rule, but it’s so common a pattern that keeping it in mind when making security decisions (to avoid fulfilling it or at least weigh risks) is a good practice.
As soon as the word “convenient” is used, you know it will affect security.
Yep, they technically didn’t claim it was to make it more secure.
This is always the tradeoff. Security must always impose a cost.
Why do you think that? Public key authentication systems are invariably more secure, and a wide variety are also simpler for the end user to use.
It’s a misconception that they are in opposition to each other. Why would they be? One’s about knowing who’s doing something and the other is about how much effort it takes to do it.
Public key authentication is more secure than nothing, and is more convenient than shared secrets and symmetric encryption, but bit for bit the secret material necessary for public key cryptographic schemes to be secure is more data than is required for symmetric algorithms.
But more to your point, public key cryptography is basically a usability nightmare. In order to talk to anyone you need to first validate their key using an entirely out of band scheme you already trust, and if you don’t do that then all the end to end encryption in the world is theatre.
Of course I’m being hyperbolic, it’s the internet, but seriously there a lot of people feeling secure with public key systems that are either totally insecure, or could be insecure and they wouldn’t know, or are secure to some random bystander but insecure to people and organizations that are often included in people’s threat models.
Because in general, making things more difficult for an adverse party has great potential for also having side effects for proper users. And conversely, making things easier for proper users very often also makes it easier for adversaries.
You’re right that it’s not a strict 100% rule, but it’s so common a pattern that keeping it in mind when making security decisions (to avoid fulfilling it or at least weigh risks) is a good practice.