No it all really changed when storage service manufacturers realized that they could market 1,000,000,000 bytes as "1 gigabyte", to people who then saw their computer tell them that there was about 7% less than a gigabyte in there.
Can't say when they started using it, but gigabyte external hard drives would be about when the gap got large enough normal people started to notice it.
Yup, this is when I started to really notice it too.