I mean, you're not wrong and it is open source at the app layer but it's not like Raspberry Pi is a purely software product. They're a hardware company, acting like a maker friendly, open source device - similar to Arduino (which btw is totally open source, even the bootloader and you can get data sheets for every single component on it), but it falls short with only the top app layer being open source. The middle layer (HAL, drivers, etc.) is all closed source. And hardware is closed source.
It's ok to be closed source IMO, but they should not be marketing themselves like Arduino folks.
It's ok to be closed source IMO, but they should not be marketing themselves like Arduino folks.