Device full but all is saved to iCloud….?

Hey there and welcome to Apple Support Communities tgriner21,

We can certainly understand your concern and see you came to us from the article Manage your photo and video storage.Have you ensured that Optimize iPhone Storage is on under Settings > Photos?

If it is, when you go to Settings > General > iPhone storage, make note of how much storage space the Photos app is using. Then, compare it to how much is being stored in iCloud: Check your iCloud storage on iCloud.com - Apple Support

Please let us know the results when you're able.

Kindest regards!

Then you're likely out of space on your device.

Have you optimized photos? Settings > Photos . Please know that you may need to free some space on your device too if it no longer syncs.

Remember, iCloud is primarily a synchronization service, not offline storage. When you enable iCloud on your device, your content remains on device and is synced through iCloud to all of your other devices.