Does getting all resources of a type make an individual call for each Resource Group?

This is more of a question/feature-request than a bug.

In the below method and similar others, to list all resources of a particular type, will it make different REST calls for each resource group? If yes, Is it not a performance concern? Why can’t we make a single call using filter API with resourceType filter across all resource groups in a subscription?

public IEnumerable<IVirtualNetworkGateway> List()
        {
            return Manager.ResourceManager.ResourceGroups.List()
                .SelectMany(rg => ListByResourceGroup(rg.Name));
}

[hovsepm]

I think we need to expose List method on GenericResource that will accept Odata filter string expression. Please upvote for prioritization.

[hovsepm]

Closing as by design for current stage.