Corporates understand that a strong economy is important for the system to be viable long term and that some kind of middle class is a necessary part of it, which they can skim off the top of. Oligarchs don't care about that nearly as much, and are more acutely focused on accumulation of power and wealth and are happy to disassemble productive capacity and force the middle class down to an a working poor class in the process.

It's basically the difference between "every one of my workers needs to be able to buy one of my cars" industrial Fordism and what Varoufakis coined techno-feudalism, which does not utilize markets or independent workers but tries to extract value from what are effectively serfs directly. Zuckerberg et al. are obviously emblematic of the latter.