As far as permissions go, Calendar, Contacts, Camera, and Location make no sense. Fuck off Valve.
File storage makes sense for uploading and saving attachments. Microphone makes sense if and only if it supports voice chat. Call information is the same thing; tapping into the native Call API means Bluetooth earpieces/car handsfree, proper call audio volume, and the proximity sensor screen-off functions work seamlessly like a real call. Discord does the same thing.
Document storage is used for saving auth tokens and other misc app data, it's harmless.