I didn't really, I had doubts myself. I say the are credible based on my own understanding of how OS usage changed, being there myself at the time.
This is a classic example of a confirmation bias. How would you know the statistics from that time? Based on anecdotal observations from 20 years ago?
Your experiences were biased by being someone technical, windows was widespread, I know of a place still running XP as recently as Oct 2021 tho... there are some business that don't take updating seriously, so what you saw is not evidence of the general population.
Back to the point, it's best not to rely on your feelings when it comes to judging ChatGPT's accuracy