There are some communities that consider them to be slurs against neurodivergent people. There’s definitely an argument to be made there but at the same time they’re so commonly used to refer to neurotypical people as well that it’s also easy to argue that they don’t do enough harm to be considered slurs.

I also didn’t know there was a dark mode, but if you ever find a website that doesn’t have one I highly recommend the Dark Reader browser extension, I’ve been using it for years and it’s never let my eyes down.