Normally I'd agree with all of your points but the article is really clear about lowing the page brightness and not the page contrast. They even had an infographic to illustrate their point: https://miro.medium.com/max/1400/1*xOhOFGLr6o4AsGhlACweSQ.pn...
At no point were they making any of the suggestions the GP are criticising them for.
On the contrary, I find that the "vitriol" was a good balance to the "rage quitting" disclaimer raising the rage level for no reason. It's an article about text legibility. We should be able to take it or leave it or refute it without rage.
(Whether they rage quit or "merely said they almost did" is same difference).
Second, accusing posters of not reading articles is against the Hacker News guidelines.
Third, I bring all this up because the vitriol of your comment is no fun to read and brings down the site.