For the same reason browser vendors abolished the <marquee> and <blink> tags, this kind of unreadable color schemes should be reset by default by browsers, just like autoplaying videos, and pop-ups are suppressed.
The Gopher renaissance can't arrive fast enough.
Authors pay heed: Presentation matters. If you present your writing poorly, it will distract your readers from your ideas.
This is a third-party news aggregator. It's very common that the submitter is not the author. So the author is usually not even in the vicinity to hear the complaining. All in all, just another manifestation of slacktivism.