[ReAzem]

Now would it be possible to make something like this for GPG?

[ghishadow]

https://www.funtoo.org/Keychain can do both gpg and ssh

[BeefWellington]

A simple wrapper around pass might do the trick. Someone just needs to implement an agent that does this (tho I'm sure someone out there is working on it).

[encryptluks2]

GPG already allows you to authenticate and your SSH key is protected by GPG.