It means, a slow destruction, a quick fix. So, something was slowly destroyed but it is quickly being fixed again. For example, global warming destroys the environment slowly. But if factories immediately completely stopped burning fossil fuels, this would speed up the process of fixing the environment again.

Video recording analogies have entered the language. The writer is using language that applies to a video player. He's using it in a colorful, creative, original way to express an idea. A video player can be used to play a recording in slow motion, and then can be used to "fast-forward" rapidly and speed things up. Some kind of "demise" came on slowly and gradually, "in slow motion," like watching a video of a building demolition and setting it for slow motion so that it seems to take forever and you can see every detail. There is then some kind of repair that was very quick, that took much less time than the "demise"--so that it seems quick, effortless, and instantaneous, like "fast-forwarding" ahead. I guess all that he's really saying is that the contrast between the slow demise and the fast repair seems as big to him as the difference between "slow motion" and "fast-forward" on a video player. Video player analogies are fairly common. Someone talking about history, instead of saying "We've discussed the American Revolution, now let's skip ahead and talk about the War of 1812" might say "Now let's fast-forward to the War of 1812."