One problem that I often encounter is that people either don't use Google Photos/iCloud, or they don't have sufficient free space in their cloud storage account to upload photos/videos. Additionally, in the case of Google Photos, if the person has configured Standard Quality for their personal account backup, the shared photos will not be in the original quality.

You might want to browse through this HN post about Google Drive losing data that's on the front page at the same time your AskHN is:

https://news.ycombinator.com/item?id=38431743

within the comments, there's people also complaining about losing photos as well. just so you're fully informed