Vault requires a non-trivial amount of setup and configuration, and then you need to configure SSHD to use it. You also have to maintain the vault server, HA, y

Vault requires a non-trivial amount of setup and configuration, and then you need to configure SSHD to use it. You also have to maintain the vault server, HA, yada yada. And educate people on how to use it. Vault truly shines in its ability to provide ephemeral credentials. It can even "package" arbitrary secrets for you, and ensure that they are only ever retrieved once. It's a fantastic piece of software, one that more companies should be using, but it is not a push button deployment. It is borderline impossible to implement in many 'traditional' organizations.