This appear to be a window system and desktop environment than OS, but isn't it that ESP32 user code always runs atop FreeRTOS for radio management purposes?
FreeRTOS itself is very barebones, a library that provides basic memory management, task scheduling, io and a TCP stack, but not, for example, an abstraction layer for screen, keyboard or other peripherals, or the concept of running user applications.
Espressif ships the wifi driver also as an .o file that takes huge struct of function pointers to OS-provided functions that works with other RTOSes. But you need some kind of RTOS.
