The DIYers that bought the 9900K series were predominantly bleeding edge types. They overclock, use expensive cooling, and move on to the next best thing when it comes out. Hardly simpletons by any metric.
But yeah, 9 series does not hold up against the 5000 series. And the 3D version absolutely starches it as Steve demonstrates. Would have enjoyed seeing the 5600X3D on the charts just for giggles.
As I have pointed out; there is a reason AMD has 70% share in the TPU poll. And why almost as many respondents are using AM4&5 Zen 3D, as all Intel CPUs combined. I.E. Most of us are building gaming PCs. AM4 is 7yrs old in February. The competition was the 7700K. The platform still being relevant after all these years? It's nuts if you think about it. And for anyone that doesn't think it is still relevant, pay attention to Zen 3 sales. Particularly come Black Friday through the rest of the holiday deals. Still consistently dominating the top 10 on Amazon too. Doesn't get more relevant than that.
I will close with a joke. To keep up with AM4 on Intel, you had to change boards and CPUs more often than a hobo changes underwear.