Arctic Cooling Silver 5 and eventually the MX-4 was the default choice for thermal pastes mostly because it was available everywhere at a reasonable price. Every enthusiast had one. Even if CPU coolers back then came with goo in a small pouch, these were the preferred choice. The Silver 5 was a conductive thermal paste, while the MX-2 was the enthusiast first chance to get a non-conductive thermal paste and also it practically did not have a curing time. Because of which a lot of people adopter pea and line application method easier than they would. I don’t remember all of the series of events, but that’s the basic story you’d get to see here in India.