Have you read the article?
The problem isn't just the metadata leak, far from it. Some problems mentioned:
1. PGP is old and broken and messages can potentially be decrypted without access to private key
2. Because email's default is plain-text, in real world conversations you end up with people replying in plain text with your whole message being quoted
3. Archived messages will leak. An e2e channel needs to have a way to inform receivers that messages should be deleted after some time
4. Private keys eventually leak, therefore it is important that when it happens, the system makes it hard to decrypt old messages (by combining it with ephemeral keys).
So if you have login credentials to send to someone, if you value that info and I assume you do, otherwise you wouldn't use PGP, then this is precisely the use case that encrypted email is terrible for.
PGP usage is also very user unfriendly so you’re not losing anything really,.
The problem isn't just the metadata leak, far from it. Some problems mentioned:
1. PGP is old and broken and messages can potentially be decrypted without access to private key
2. Because email's default is plain-text, in real world conversations you end up with people replying in plain text with your whole message being quoted
3. Archived messages will leak. An e2e channel needs to have a way to inform receivers that messages should be deleted after some time
4. Private keys eventually leak, therefore it is important that when it happens, the system makes it hard to decrypt old messages (by combining it with ephemeral keys).
So if you have login credentials to send to someone, if you value that info and I assume you do, otherwise you wouldn't use PGP, then this is precisely the use case that encrypted email is terrible for.
PGP usage is also very user unfriendly so you’re not losing anything really,.