I don't know. There are kids making games in Roblox now, editing movies and doing all kinds of things, but Hacker News would still consider them "nontechnical" because they have social media accounts.
Maybe the inflection point was the transition between Windows XP and Windows Vista. In XP, the default behavior was to show file extentions in Windows file explorer. In subsequent Windown releases, file extentions for known file types were hidden by default. This led to future generations being less capable of identifying common file formats. Computer illiteracy has been snowballing ever since.
https://www.brainbell.com/tutors/A+/Hardware/Managing_Files_...