Ever since the "viral social internet" became a thing, so around the time 9gag launched, I guess, I've been bothered by sharing things as screenshots. Not just because sharing a screenshot of an image usually adds black bars and reduces resolution a lot. Mostly due to lost accessibility of the content, especially when sharing text content. Most social networks don't allow custom alt texts, so blind users are at the mercy of platforms to OCR contents and set the alt text.
Oh, and don't get me started on lost semantics of the content. An alt tag is useless at conveying complex semantics of image contents. Just use text when you want text.
I know that the reason most people/brands will post screenshots of posts on other platforms, is because conversion rates of images are much better than "unexpanded" links to other platforms (which your average client will show). Plus, if the original content is deleted (for whatever reason by whatever entity), a screenshot will still exist (and thus make you vulnerable to a ban?). There's also the immediate benefit of citing your source when using a link instead of a screenshot.
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