Admin edit: While this cannot become a built-in feature, you may find useful the following example: https://github.com/telerik/blazor-ui/tree/master/common/grpc-example
As .Net Core 3 offers gRPC support, I'm suggesting that the Blazor Team, look into some of the components that could automatically talk to backend gRPC services to get data, i.e. Auto Complete or DropDown box.
This way it could simplify different ways of providing datasource to some of these data oriented components.
Hope this suggestion helps!