While the ESP32 is great for many applications, it’s not for battery operated stuff. When an nRF draws 1-2 mA when using BLE, ESP32 will draw 40 mA. And the chip they selected is even more efficient.
The low power chips can also run in low power mode without BLE running using micro amps, something the ESP can’t match.
I really like ESP32 and I hope they have a low power chip on their roadmap.
Sure I agree, but the WiFi functionality is a killer feature. As mentioned in another comment, it means a smart watch stops being a smart phone addition and can actually operate as a stand-alone device.
Years ago I had a "smart" watch that had a sim card and was a full mobile phone within its own right, I think it was just 10 years or so too early.
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.
Of note, you can just pull in a lib to use Wi-Fi and BLE on an ESP32 (C-3 at least). I've done it. It doesn't imply any changes to your firmware architecture. That's the part that bothers me about Nordic's approach.
The low power chips can also run in low power mode without BLE running using micro amps, something the ESP can’t match.
I really like ESP32 and I hope they have a low power chip on their roadmap.