Alt text is meant to convey the information or context that sighted users get from an image. But if your alt text includes extra information that isn't in the image, you're giving screen reader users additional context that isn't conveyed to people not using screen readers.
@scy Alt text is meant to give screen reader users the equivalent content and context that sighted users gets. If a picture shows people waiting in line outside of a polling place, the alt text can say that and describe the picture in some detail. But there are some things that sighted users couldn't possibly get from that image: how many hours that polling place was open that day, how many people came in total, etc. That should go in a caption, for everyone to get, rather than the alt text.
Avoid using images of big blocks of text. Using actual text instead of images of text will help screen reader users, but also will help people with reading disabilities. Using actual text helps users who need to adjust the text's font, color, size, and alignment.
Hi David, thanks for reaching out. The point of accessibility is not to "avoid doing anything that seeing people might enjoy." A chart that is made with HTML and CSS can be just as visually appealing as a chart made that is a static image. Furthermore, that chart can appear in more screen sizes, not to be mention also be customized by people using assistive technologies. A lot of things can be rendered using HTML, CSS, and images, avoiding static images of text.
If your comment was not meant to be snarky or troll-like, there are journalists working to make news sites more accessible to people with disabilities. There are visual journalists who able to create things that "seeing people might enjoy" that also can be used by people with disabilities. They don't have to be mutually exclusive.
In your neck of the woods, Joe Amditis of the Center for Cooperative Media is doing some great work demystifying accessibility.
When writing alt text, be specific but also succinct. Stick to as few words as you can. Is the clothing relevant? Is the color of the plate important? What about the weather in the background? Decide whether this info adds or distracts from the context of the image.
@losttourist I would argue that the example you gave fails to be good alt text, for the reasons you listed. I think that the goal should be to be as specific as needed while being as brief as possible. Write as much as you need to, but no more. And I think that example fails at that, again for the reasons you outlined.