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.