AI can help with that. Facebook already has automatic alt text for images, for example:
* Image may contain: 1 person, standing, selfie and phone
* Image may contain: cat
* Image may contain: food
And for an end-user, simple filtering can help with that. I sometimes use the FBPurity browser extension to hide everything that's a link or shared post, leaving almost exclusively original content. It can filter on that automatic alt text too if you hate cats, but I don't mind frivolous posts that are original content from my actual friends.