People don't like rapid change when it's applied to them against their will, when it's coercive, and when people don't like something, an external stimulus, they tend to kick back against it. Religious fundamentalism boils down very largely to one thing: certainty in life.
There are several problems with this thesis. One is that "progress" (generally defined) has been ongoing since... well, really since time immemorial, but the most obvious point to date it from is the Industrial Revolution. Once that got started in earnest, each generation saw a clear rise in living standards and technology from the previous one (prior to this point, technology advanced slowly enough not to be disruptive during a single generation). But religious "fundamentalism", by which I assume Stross means a rejection of the Enlightenment and return to safe religious dogma, has not risen in step.
A second problem is that Krugman and Stross just finished saying in the prior segment that we haven't seen much rapid advance in technology if the past fifty years - that it has flattened out. But if that's true, then where's the shock?
A third problem is that their terms are horribly biased. "Religious fundamentalism" is really a poor name for the general movement to reject the Enlightenment. This movement can be traced back to the Romantics at the start of the 19th century, and continues into Postmodernism. But when Krugman is talking about "religious fundamentalists", he's not talking about that. He conflates (a) Islamic fundamentalism, which traces back at least to the Wahhabi movement, and probably could be traced pretty easily back to the point at which the Islamic clearly was losing supremacy to Christendom (the Battle of Lepanto in 1571? the siege of Vienna in 1683?); (b) Jewish orthodoxy, which he claims has been on the rise recently among an "amazing number of relatives of [his]"; and (c) Christian (mostly Protestant) fundamentalism, which he traces back to the rise of radio in the 1920s. Is it really possible that each of these really reflects "future shock"? They seem amply explained by other mechanisms. Maybe future shock is some sort of meta-mechanism underlying everything, but Krugman and Stross are not at all convincing that this is the case.
A final problem is in the assumptions: people don't like change when it's coercive. I think that can be simplified to: people don't like being coerced. But regardless, what does that have to do with technology? Technology doesn't coerce. If a person doesn't want to use a computer, he doesn't have to. There is social pressure, sure, but that is not coercion. I think some people may not like technology (or more properly: that which it represents, i.e. the Enlightenment) and react against that, but that is not what Stross was saying. Coercion in our lives might be coming from the large faceless corporation we work for, or the enormous governments we fund with our taxes. But that isn't future shock.