Why does Babel use setPrototypeOf for inheritance when it already does Object.create(superClass.prototype)?

Question

Posting the following code into the Babel REPL

class Test {

}

class Test2 extends Test {

}

you get this inherits function

Answer 1

The setPrototypeOf does set the [[prototype]] of subClass from its original value Function.prototype to superClass, to let it inherit static properties from it.

Object.create cannot be used here (like it is for the .prototype object), as it does not allow to create functions. The constructor of a class has to be a function though, obviously; and the only way to do that is to create functions using standard expressions/declarations and then change its prototype afterwards.