Insulin resistance is defined by abnormally high blood glucose concentration in the presence of insulin. It may be true that for sedentary people who consume a typical western diet, abnormal is "normal" but that doesn't justify the statement "everyone has insulin resistance to some degree".
As for "spiking" insulin levels as the cause for insulin resistance, that is hardly proven. Inflammation has been shown to directly induce insulin resistance. Current evidence seems to indicate the problem is blood glucose levels remaining elevated (despite elevated insulin); this happens because there is a limit to the rate of receptor mediated transport.