To be absolutely clear, your iCloud backup is incremental.
iCloud does not maintain multiple full backups of any single device. This strategy, whilst lacking the functionality that you seek, provides a fast/efficient backup of your device(s).
If you wish to keep multiple full backups of your iPad, you’ll need to use a PC (with iTunes installed) or Mac (with iTunes or Finder) as appropriate the installed version of macOS). Having created a device backup, it will need to be manually archived prior to creating a new full backup of the device. In addition to lack of automation, the time required for each backup will be considerable - in direct proportion to the amount of locally stored data.
Individual files, data and photos that are synchronised with iCloud are not included in your iCloud backup. Instead they are accessible using the iPad Files App - or from another computer using a web browser:
https://icloud.apple.com
As such, unless your social media interaction creates discrete files that are stored/synchronised in iCloud file storage, you’ll not be able to recover them.