There is no singular definition of HFT. The extreme end of low latency is really only applicable for market making systems, but there are plenty of systems in t

There is no singular definition of HFT. The extreme end of low latency is really only applicable for market making systems, but there are plenty of systems in the HFT sphere that do not rely on market making latencies. For example, those microwave links you're talking about? Those are specifically for cross exchange arbitrage. In that domain acceptable latencies go up quite a bit, and general purpose computing is still quite competitive.