The validate command will download dependencies of the extensions that are being validated, as shown in the addDependencies() function: https://github.com/crossplane/crossplane/blob/release-1.16/cmd/crank/beta/validate/manager.go#L191-L205

However, this dependency resolution only goes to the first layer of dependencies - it does not go deeper into the full dependency graph. So if package A depends on B which depends on C, that 2nd layer of dependencies with package C will not be downloaded and cached.

We should download and cache the entire dependency graph, so we have all the schemas for validation.