Not sure whether Karpathy meant it like that or thought about this statement being interpreted this way, but I totally agree with you. Creating animated movies and special effects is placing a lot of 3d polygons by hand. Maybe not with JavaScript though. However, people also made things like

telnet towel.blinkenlights.nl

Now, were they „in their right mind“? I don‘t know. The more likely explanation is they found joy in it. Reminds me of what the Suno CEO Mikey Schulman said about making music: „[…] I think the majority of people don’t enjoy the majority of time they spend making music.“ (https://news.ycombinator.com/item?id=42688538)