I'd say PlatformIO is a better analogy -- a framework that lets you use virtually whatever HAL you're familiar with (Arduino, Zephyr, freeRTOS, mbed, etc) with

I'd say PlatformIO is a better analogy -- a framework that lets you use virtually whatever HAL you're familiar with (Arduino, Zephyr, freeRTOS, mbed, etc) with whatever hardware and its corresponding toolchains.