How is this different from a website valuation calculator?

A valuation calculator gives you a number from traffic and revenue inputs, usually in about four seconds. That is a useful sanity check and it is not measurement.

The difference is what happens to the parts that cannot be filled in. A calculator substitutes a default and returns a confident figure anyway. This framework leaves the gap visible, because knowing which dimension you have no evidence for is more useful than a number that hides it.

The other difference is that nothing here produces a single figure at all yet, deliberately.