Yes, it's an effort to standardize and future proof.

Cloudflare's post [0] has some more background information.

[0] https://blog.cloudflare.com/hybrid-public-key-encryption/

Just from a quick scan of the RFC: this seems to generate the encrypted session key directly from the public key of the recipient somehow. This also seems to be an attempt to standardize generating the public/secret keypair from something like a passphrase.

Traditionally you generate a random session key and then encrypt it using the public key of the recipient. The public/secret keypair is generated standalone where you optionally encrypt the secret bit of the keypair separately with a passphrase.

Not yet sure how this scheme would work in practice and what the advantage is...