What does this mean in the larger landscape though? Every company is using AI or trying it out, are they not using the cloud services for it? If so is it still not a big enough pie to show?

It means it is very fragile. Now if you consider that this probably Nvidia's money doing a circuit, it looks even more dicey.

If Microsoft only has 1 customer, and that customer blows up/fades away, what happens to all their capex?