Aside from the fact, already highlighted by other commenters, that this is a proprietary system operated by a company that actively protects their IP, I think it's also a terrible idea.
As you noticed, it does not differentiate based on height, so the ballyhooed deliveries would require two addresses to find an appropriate suite number in an office building, but more importantly, their app is required in real-time to find anything.
Given an address like 123 Main St, I know that I can find Main Street, and then head in one direction or the other to find 123. Given an address that is three arbitrary words tells me absolutely nothing about where that is in relation to me. Zip, zero, zilch. Only an app, or a clumsy proprietary printed map, can help me. Even then, anything other than following arrows on screen is a genuinely ugly experience.
A public, open address of the traditional variety lets one get close, then closer, and zoom in based on the address alone. In the US, for example, you can first read the country, then the state, then the city, then the street, and finally the street number. It's all stored pretty efficiently in a standardized address.
This dumb system loses all of that, but they claim it's better for places that lack standardized addresses. Of course, we already have a system for that: latitude and longitude. The advantage of the public, open lat+long system is that, again, you can generalize and approximate at first, and then add more decimal points when it matters. There is no way to do this with this dumb system.
It's an idea that seems great when you first encounter it, but it's proprietary in a way that hampers its utility, and is also impractical in actual operation.