I have some pictures from 2019 that I took on a disposable camera that are starting to collect these strange pinkish-dots all over them. The photos: https://imgur.com/a/WGY9TY4 For some context, these photos were pristine up until a few months ago. These photos have been stored on the wall in a room that gets a half decent amount of sunlight but the photos aren’t facing towards the windows at all. What could be happening and how can I prevent these photos from further degradation?
If you still have the negatives, get them scanned.
If you don’t have those negatives anymore, get your photos scanned asap and retouched to remove those defects. Some could be easy to remove, some could be a bit more challenging depending on the location in a picture (removing a red dot in a blue sky is way easier than removing those on complex structures).
It could be chemicals not washed out during development (as someone else already mentioned), could also be dust particles (like some chemicals in powder form, concrete dust, …) in combination with high humidity.
If you print images to have them last long (really long like tens of decades) have them printed with Canon or Epson fine art peinters on high end papers. Chemically developed prints will fade way faster. (source: Wilhelm Image Research)