This is NOT a Blynk related issue, rather it is the normal operating mode for a high powered, BLE/WiFi enabled and constantly communicating MCU.
Google (and search here) for ESP32 sleep mode options… No, sleep is not ideal for use with Blynk’s BLE option, but it either runs hot and draws current as normal, or sleeps and briefly wakes intermittently as needed (Usualy with WiFi, but probably possible with BLE??.. As said, Google for more info on this)