Home computers were initially a novelty item, sold mainly through direct-response advertisements in magazines like Popular Electronics. This early hobbyist market created the economies of scale that made a mass market home computer a possibility.
In the late 70s and early 80s, most people simply had no idea why they would want a computer; The first home computer adverts in the mainstream media didn't really sell the benefits of one computer over another, but sold the idea of the computer:
Without that kind of advertising, it's entirely plausible to believe that home computers might have been a fad, with the computer resigned to being a specialist tool for business and industry. There's a parallel universe where the home computer and video game boom never happened because nobody told consumers why they might want a computer, the 6502 and Z80 remained niche microprocessors for embedded applications, Woz went back to HP and Bill Gates finished his degree and got a job at Honeywell.
The fact that people were already reading about electronics in magazines they bought with their own money shows that people would have known what computers were regardless. Those advertisements only worked because the audience was already interested in computers. Those computers also already existed and the notion that no one would have used a computer if an ad didn't tell them to is absurd. Computers exist because they're useful and fun and they were purchased by people who wanted computers and were willing to seek out products they wanted.
In the late 70s and early 80s, most people simply had no idea why they would want a computer; The first home computer adverts in the mainstream media didn't really sell the benefits of one computer over another, but sold the idea of the computer:
https://www.youtube.com/watch?v=Q7_j_ABrkn8
Without that kind of advertising, it's entirely plausible to believe that home computers might have been a fad, with the computer resigned to being a specialist tool for business and industry. There's a parallel universe where the home computer and video game boom never happened because nobody told consumers why they might want a computer, the 6502 and Z80 remained niche microprocessors for embedded applications, Woz went back to HP and Bill Gates finished his degree and got a job at Honeywell.