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.
If you're a software engineer/programmer and have never seen/interacted with a visually disabled or blind person using their digital device, I highly recommend it. It's extremely interesting and will help you understand why it's the small design decisions you make that can impact them a lot. Even if you build products for "professional" markets where accessibility is (sadly) not a selling point, use it as a decision maker when you have the freedom of choice.
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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