ASCII armored exports suitable for plain text copying and pasting and inclusion in other documents and messages seem to be the norm for sharing. Keys are referred to by keyid or email. To the key database, files seem more like an implementation detail.

It provides the tools necessary to implement a simpler workflow.

The term E2EE has been subverted. Apps like WhatsApp claiming to be E2EE, but only if you actually enable it, so that people think they are being encrypted when they are not does not help. ProtonMail falls into this as well where allowing email to non-encrypted addresses means there is no encryption. It's obvious to some, but not so for the majority. Very few people read the caveats that WhatsApp and ProtonMail provide.