In the sense that those processors can compute things which are computable, yes, they are a real alternative. The correct question is, "How much worse would the situation have to be with Intel before the cost of these alternatives was less than the benefit of switching to one of them." The answer, I guess, is: "much worse than things are now." However, if you're running at billions in revenue per quarter, you can afford to spend a few million to limit your downside risk by keeping yourself apprised of what the costs would be of moving to another platform.