This is according to the official product manual for the console that was discovered by @Renka_schedule on Sony’s Japanese PlayStation website. Based on this manual, it sounds as if Sony is working on refreshing the current Digital Edition PS5 and it seems that some of the changes Sony is making under the hood will result in the new model being 300g lighter.
The original Digital Edition comes in at a weight of 3.9kg, but this new model is said to be 3.6kg, meaning that Sony has shifted some things around inside of the console and removed certain components to help it become lighter, although we can’t be sure what kind of changes they made.
Sony CFO Hiroki Tokoi did state earlier this year that they are looking at ways to address the current global semiconductor shortage, such as redesigning the console, so maybe this new model could be that redesign Tokoi was talking about.