The PlayStation 5 console has three different power states: On, Off, and Rest Mode - but there's also a fourth mode that modifies the On state, called Power Saver.
You can read more about about Power Saver on the PlayStation Support Site for details on how to turn this mode on and off. Keep in mind that this mode is limited to games that specifically support it, and some gameplay features may be limited.
Currently NBA 2K27 supports Power Saver Mode.