I'm not blind or have impaired vision, so take this with a grain of salt (feel free to correct me), but people who put nondescript one sentence alt texts are almost worse than those who put no alt text.
At least if I'm about to boost a picture without, glitch-soc will warn me about it. If a picture has an alt text like "screenshot of my tweet", that's less than useless but it will slip through the alt text detector.
Write good alt text ffs. Describe the picture. Not a title or a TLDR, a proper description. If it's text, copy the text into the image description. If it's selfies, don't write "a selfie of me", describe your selfies. Describe film scenes, descripe paintings, descripe charts and infographics. You have, on this instance at least, 1500 characters to describe your pictures. Do it.
And if 1500 isn't enough, you can add a second picture to keep describing it.
#feditips #accessibility #alttext