In addition to the regular ESP32 benefits (BT, BTLE, dual core, etc), the TinyPICO is REALLY small and has really good power consumption in deep sleep mode. A lot of the random Aliexpress boards have power consumption on the order of 10-100 milliamps in deep sleep. The TinyPico is more like 20 microamps. Part of that is through higher quality parts (presumably better voltage regulator, battery controller, etc.). Part of that is through a more thoughtful design (instead of having to desolder an annoying always-on LED to reduce power consumption, you can just turn it off in code).