Imagine, for a moment, that your internet just stopped loading images one day. Your dash might look pretty different (and less usable), but at least you can still make posts — whether about your internet situation, or about completely unrelated topics.
Now, imagine that one or more of your posts blew up, to the tune of hundreds if not thousands of notes. Imagine people started adding images to your posts.
Imagine your post circulating almost entirely in the form with four or five images attached, and with everyone in the notes laughing about those images — except you, who started the post in the first place, who can't even see those images because you're trapped in Tumblr's loading gradient hellscape.
You're excluded from any further conversations on your own post, because someone added a mystery image with the caption "don't leave this in the tags," but you have no idea which set of tags it is, and can't tell if it's one of the good takes from the tags or one of the horrible takes from the tags. You're excluded from the Tumblr users playing with JPEGs like dolls. You can try to guess the contents of the images based on people's reactions, but it's hard. And no one adding images even seems to notice the irony.
This is, of course, a real problem plaguing Tumblr users with regularly slow internet. And it's also a huge, insidious problem plaguing blind and low vision people who rely on either screen readers, or image descriptions in combination with enlarged text on their device.
People with disabilities around comprehending images, people who have images (or gifs) disabled due to photosensitivity, and many others are also affected.
If you add an image to a post without either alt text, an in-post image description, or even both for maximal inclusivity, you don't know if OP — or the person whose tags you're peer reviewing, or whose reply you're screenshotting — will actually be able to see it. From their perspective, you might just be shoving a mystery rectangle in their face, expecting them to be able to guess — or responding to them without them being able to know.
Imagine being on the receiving end of that expectation constantly. Imagine how isolating that must feel.
We need, collectively, to stop making assumptions that everyone we interact with online will be able to access, physically see, and mentally process images. The assumption that disabled people are vanishingly rare and statistically shouldn't really need to be considered is an assumption of structural and/or implicit ableism.
Write image descriptions. Write image descriptions for every image you post, if you're able — but if you have limited energy, or you're still learning, you should at least start trying your absolute best to describe images you add to other people's posts. If you're starting a conversation, even an online conversation, you should make your best effort to be accessible.
So: Write IDs, especially if they're as simple as just text, like screenshotted tags (link to guide). Write IDs even if you think the best ID you can write is too short, or too incomplete (link to post explaining why even "bad" IDs help).
Write IDs in general (link to a huge compilation of guides). Challenge ableist assumptions and inaccessibility.
