Screenshots of text preserve the state of the text at the time it was seen…
Yes, it’s not good for accessibility but it’s a good way to quickly capture a moment in time.
(I would recommend perhaps also copy/pasting a synopsis for people who might be vision impaired etc)
Also, modern tools are getting pretty good at dealing with text embedded in images. It isn’t ideal but this partially mitigates a large concern (accessibility). Rather than complaining about people taking screenshots maybe pressure should be placed on the screenshot tools, and image formats, to better capture the raw text exactly and embed it as extra data along with the image.