The PS5 received update 7.00 yesterday, which brought a ton of new features, some of which were hidden, like the common save file format between PS5 and PS4 games.
In case you have downloaded and installed a game on PS5 that you previously played on PS4 and previously uploaded the save files to the cloud service within the PlayStation Plus service. After downloading and installing this game on your PS5, you will receive an alert informing you that the save files for the game from the PS4 version are available. And by pressing the main PlayStation button on the console, you will be able to download the save file and transfer it to the PS5 version and complete the game from the point you set on the PS4 version.
In other words, you won't need to use an external USB storage device to transfer game save files from the PS4 version to the PS5 version.
And vice versa, as the user will receive the same alert if they are playing a PS5 game with a special copy on the PS4 device, and will be able to transfer the saved file to the game and finish the game through it.
With this step, Sony is trying to increase the degree of harmony between its old and new platforms, and although it did not live up to the level of harmony presented by Microsoft on the Xbox Series devices, it is a good attempt to improve the experience for users between the two platforms.
There are a lot of new features that are now available in the new PS5 update #7.00, most notably full connectivity with the famous chat platform Discord and the ability to wirelessly update the DualSense controller without the need to connect via a USB cable.