Most modern companies don't need cheap computing. They have a lot of users generating revenues, and they usually need little computing resources.
Google always worked by giving everything free to people. (Google, Gmail, Maps, Youtube, Android, Chrome). And they have extremely infrastructure intensive applications to run (e.g. just gotta copy the entire internet to index it + serve years of videos per second :D).
For every paid click/page a user will see, he will go through hundreds of page paying nothing, and Google will have to make thousands of pre-computations to be able to serve it in the first place.
That's the world Google lives in. They had to be hyper efficient since day 1 or they couldn't survive.
(Also note that they started > 15 years ago. The available hardware was 2^5 smaller at the time).
Google is probably the one company is most dependent on their computing efficiency.
Google's most prominent products are possible only because they could deliver those with the unprecedented computing efficiency. This is not to be found anywhere else. For example, search, Gmail, Youtube.
Before AWS, Amazon care about efficiency. But fundamentally, Amazon do not depend on computing efficiency to support the company's bottom line, or at least only in a degree that is far less important compared to Google.
They depend on cheap computing in the sense that they only pay for what they use and don't have upfront capex costs but I don't think thats what GP means. Google initially grew by filling data centers with commodity consumer computers instead of "enterprise-grade" servers and now they have cheap computing in the form of ASICs and highly customized/integrated general purpose servers.
