For one, many people prefer to browse websites with javascript turned off. Aside from performance benefits, you turn off user tracking, flashy ads, autoplay videos, annoying popovers, etc.
only one person blocks JS: false
therefore many block JS
I would expect that the percentage of people who browse without javascript on is incredibly small. The absolute number might be largish, and I guess in that context is could be considered "many."
Still, the vast majority use javascript.