I'd posit that happens not because your connection is too slow per se, but because your Wifi/LTE coverage is spotty, and speeds on the margins of coverage can be very slow.
So the real problem is coverage, not speed.
But my point is that there's the consideration that it takes half a second to download 500Mb (roughly a 720p video). So if you have 0.5s uninterrupted that's pretty convenient. I'm also pretty positive that coverage will increase from current conditions (I don't see a reason why it wouldn't). So the speed helps with the spottines. Basically what I'm saying is you don't need as long of a connection to download the same amount. If your spottiness is the same then you get more on 5G. Alternatively since it is 10x the speed, that would be equivalent to 10x spottines (which were not considering a fallback to 4/3G).
We can already guess at some use cases. AR, VR, or other types of environment simulation. Data processing for vehicles: cars, trucks, drones. And I'm sure that people will figure out more things they can do. But the notion of "there isn't anything else" so why do we need more, is like saying 640K is all you'll ever need (I know he didn't actually say that, but the myth stands)