Facebook mobile is a suboptimal experience, which is fine, it just reminds me to use it less.
They also go out of their way to make it hard to save a photo without granting full access. Creepy.
For example, when you receive an audio message, if you want to listen to it, it will request full media access. Android apps can access media files they have created, so this permission isn't needed. But without granting media access (or tricking it into thinking it has it, like with GrapheneOS' storage scopes), WhatsApp won't let you listen to the audio. Same when trying to open an image full screen instead of just the in-chat preview.
If this were a small developer, I could assume it was done that way accidentally or to cut some corners. Coming from Meta, I can only assume malice.