I have an ESP32 also and hooked it up as I2C on pins 21 and 22 (default I2C for ESP32) and I never get a response from the scanner.  I tried UART also and still no response.  Any suggestions on how to get this resolved?  I have two of these devices and neither one works at all.  I am getting a signal on my oscilloscope from the I2C wires but the ESP32 (or your demo code) seems to not be able to use the incoming signal.

No…they are not working.  My device just changes colors and never reads any barcode of any type.