The world could run on older hardware if software optimization was a priority

Well, yes. It's an economic problem (which is to say, it's a resource allocation problem). Do you have someone spend extra time optimising your software or do you have them produce more functionality. If the latter generates more cash then that's what you'll get them to do. If the former becomes important to your cashflow then you'll get them to do that.

It's the kind of economics that shifts the financial debt to accumulating waste, and technical debt, which is paid for by someone else. It's basically stealing. There are --of course-- many cases in which thorough optimizing doesn't make much sense, but the idea of just adding servers instead of rewriting is a sad state of affairs.