>that create value which others consume.

and

> Thereby comparing revenue of a platform against a traditional business model doesn't make sense

When two entities trade, by far they do it because they both benefit. There is no difference between platforms and other businesses. Each provides value to customers, and the sum of the benefits each gains each trade (often called consumer and producer surplus in economics) is the net gain to the pair.

Revenue is a very good measure of how valued these trades are to customers. In fact, almost all customers would pay more for the benefit (up to but not exceeding their consumer surplus).