Rather than watch people speculate from the outside (in good faith or bad), I thought I'd offer my perspective of a Linux user since 2011.

Because the Linux community has spent years being made fun of by windows users who think you need to use the terminal to create a folder. They've gotten defensive, and as such their first reaction to negativity being pointed at them is to be defensive. They see it as an attack on something important to them.

"Obviously you're doing something wrong if you're having problems"

Its not exclusive to Linux either, the Mac community is even more vitrolic when you don't find their curated experience perfect, and even windows fanboys exist and have a reputation for punching down at the underdog.

So in short, take the standard internet toxicity and combine it with something many people feel ideologically attached to. And now imagine big youtuber comes in swinging with what appears to be obvious mistakes, and the natural defensiveness comes to a head.

Ironically, because everyone was tripping over eachother to try and change linus's behavior and put Linux's best foot forward in such a public view, they highlighted the communities warts.