The reason so many blogs have "stock images of people in suits doing business" is because when the article is submitted to a social media app, the app scrapes the blog looking for an image to use as a thumbnail for the link. Pages with no image, get a default thumbnail and users don't click it. The entire reason so many pages on the web have some generic image from unsplash is because of these thumbnails.

This means that the main meaningful way users will see the image is resized as a thumbnail, so before you start dithering, you should really test to see how the resized dithered image looks. Odds are good it will not look good.