?

i dont think so mate

Maybe the photographer had an unsteady focus. If you are the one having issues, try Image editing, size to 5" w x 3" h @ 144 dpi.

They've always compressed and re-sized so there is going to be some loss. Have you changed any picture quality settings in your phone lately?

Some people are also not able to freely share information (like screencapping an image to omit certain metadata due to country) leaving their media to be less than ideal.

So I don't notice anything, I think it's more about the photos that people upload. If they're overexposed or just using bad cameras. But if you take good photos, the quality after uploading is also good.

No, not to me.