Google Photos might try to leave out some images during backups to save space

Whether you are content with the 15 GB of storage offered for free by Google Photos or or have subscribed to Google One for additional space, the truth is that the capacity is not endless and you have to be mindful of how much you are backing up every day. Some file types require more space than others, which is presumably why Google is considering a new approach.
Photographers and enthusiasts prefer RAW files over compressed formats. These files contain uncompressed and minimally processed data from camera sensors. Shooting with RAW enabled captures greater details than other formats
Since a large amount of detail is stored, RAW images take up more space than other formats such as JPG, that use compression to store data. Web pages with RAW images also take longer to load and uploading them takes more time and data.
When analyzing 9.8 of the Pixel Camera app, Android Authority came across what looks like a code comment that says that RAW images will not be backed up by default. If Google proceeds with this change, you will have to enable RAW backups, otherwise, only JPGs will be saved to Google Photos.
Another thing that Google appears to be working on, but for Pixel users only, is making images with different file formats easier to identify. At the moment, when you are selecting a photo, there's no way to tell if it's a JPG image or a RAW file. The only option is to go to Google Photos and upload an image from there to a platform or website.
In the future, Google will store DNG images, which is the RAW file format preferred by most Android phones, in a RAW Images folder. They will no longer be lumped together in the share sheet, making it easier to identify the format you need.
Since a large amount of detail is stored, RAW images take up more space than other formats such as JPG, that use compression to store data. Web pages with RAW images also take longer to load and uploading them takes more time and data.
Right now, both RAW files and JPGs are backed up on Google Photos together. Google understands that RAW files burn through space more quickly than JPG images, which is why it may soon start discouraging RAW backups.
When analyzing 9.8 of the Pixel Camera app, Android Authority came across what looks like a code comment that says that RAW images will not be backed up by default. If Google proceeds with this change, you will have to enable RAW backups, otherwise, only JPGs will be saved to Google Photos.
Show option to turn on RAW+JPEG in the viewer. RAW files preserve details and offer more controls while editing. They take up more storage space. RAW photos will not be backed up by default.
Pixel Camera app 9.8 string
Things that are NOT allowed: