The log message when trying to capture in RGB888 image:

E (3776) s3 ll_cam: Requested format is not supported
Guru Meditation Error: Core 1 panic'ed (IntegerDivideByZero). Exception was unhandled.

I'm not very good with explanations, but I will do my best here. 1. ESP32 is MCU, not a computer. As such it has limited amount of memory and processing power. 2. It is just not technically possible to acquire all of the bytes necessary for 888 and write them to the PSRAM chip. Even on resolutions ...