I'm curious. Do you not like the switch because it is dispatching locally and thus might end up a with a giant switch statement or because of the String type?

Or in other words is that you would you prefer OOP polymorphism dispatch or is just that Javascripts switch case statement is weak?

Part of the problem is Javascript doesn't have ADT aka structural pattern matching which is a far far far more powerful switch-like dispatch. Elm does (maybe TypeScript as well?). But OOP dispatch (and I suppose other polymorphic types besides inheritance) are a valid way as well to do this.