There are more efficient formats like JPEG-XL, HEIF and WebP. If you convert the RAW -> JPEG -> WebP you are losing more quality. I think iPhone uses HEIF format.
But they could give you an option to change it. For example, in my OnePlus I can choose video in h264 or h265 format. Photo there is no option, just JPEG.
The overlap between "cares enough about image quality to not be okay with jpeg" and "doesn't know to install a third party app" is probably too small for most manufacturers to care about.