I agree that 'commodity' hardware will generally succeed. But, not always, and there are niches worth exploiting. For example, you mentioned PowerPC, and PowerPC in fact does well... on consoles. Which is a market worth being in.
A top-to-bottom solution - Oracle hardware, Oracle OS, Oracle middleware, Oracle DB - will have its place. It'll be a small, but lucrative part of the market. Oracle will at the same time not ignore the bigger market, including Linux. That's my guess.