I have been programming various ESP32 Cam modules successfully using using IDF 4.4 on Ubuntu 20.04.

I recently bought an ESP32-S3-EYE v2.2.

The instructions state:
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ESP32-S3-EYE does not have a USB-to-UART bridge, which may cause a problem: If the program flashed onto the board keeps the chip ...

I also could not get this to work by following the directions in the readme / menuconfig.

I did get file_serving to use the sdcard by doing the following.

1. enable sdcard in menuconfig

2. in main.c, line 87 change the esp_vfs_spiffs_conf_t struct to use /sdcard

esp_vfs_spiffs_conf_t conf ...