Concur. With nRF, you have to bolt on a separate 70002 Wi-Fi Chip.
And this chip isn't a normal QSPI chip where you read the datasheet. You have to use NRF connect, and Zephyr.
So, this brings up the obvious question: What if I don't want my whole firmware to be Zephyr nRF-connect, just for a Wi-Fi chip?
pretty sure you can use 7002 with any MCUs and vice versa. I dont know what would be the technical limitation
Manufacturer lock-in can be quite a problem. I'm not saying the ESP32 solves this fully, but you can mix and match as you like, and it's highly encouraged. I think with the ESP32 most build upon Free RTOS but I'm not aware of a strict requirement.