The documentation is very general; it should have more examples and more use cases. Basically, they just tell you the syntax without a better explanation of how to do things. We learned all of the Vault Commands (CLI) and they work fine, except when we are running on an EKS cluster then the syntax changes. Most of the commands are not working.
A Service Mesh workflow connected within Vault workflow would be difficult to integrate, depending on the SI complexity and security compliance. A drawback for some clients who have to be PCI compliant is that they still need to use and subscribe to an HSM (Hardware Security Module) solution. Compliance: www.pcicomplianceguide.org