Sometimes I do like his videos, but this one was positioned so bad. The video does go over the changes in Plasma 6.1 and they are good, but this is not a huge change that would change anybodies live.
I know he is probably inspired by channels like Linus Tech Tips, but even they don't got that far anymore. I think he probably intended this in a comedic way, as most of his audience knows that he makes his videos like this, but it really makes the videos worse.
Nice reaction for his attempt to present changes in Plasma and KDE itself somehow positive. It's pleasure to see all these dislikes. I want to think that people who do that are KDE users, because it suits perfectly to the culture of the KDE community.
Stop blaming it on some nonexistent cultural phenomenon.
People are capable of recognizing (good or bad) quality aspects of the software they use and the videos they get recommended to watch. And they are free to point out the bad ones as well as the good ones.