When did NFA items become so popular?

I grew up in North Dakota and as a kid in the 90s my parents taught me how to shoot. I turned 18 in the early 2000s and back then I had never even heard of an SBR. Visiting my family back in North Dakota from California and going to the range nearly half the people have a can or an SBR. Not the case in the early 2000s or in the 90s. I always knew suppressors were legal. My mother has a picture of my great uncle holding a modified 1903 Springfield with a suppressor attached to it dating to 1963. But again in the early 2000s barley anyone had one.