I have no experience with this board, but your problem is not likely with PlatformIO, but in hardware.
Since the ESP32-S3 processor runs on 3.3V, you might want to take a look at your boards schematic to see how the processor interfaces with the board’s USB and UART ports. There appears to be a 5V input pin, and only ESD and transient voltage protection, no level shifting.
You might try adding 5V input or interfacing your ESP32 S3 with your PC through a level shifter powered by 5V or FTDI serial adapter from one of the other ESP32 serial ports.
I have tried using the Serial Monitor from the PlatformIO CLI, but it has not worked for me. I personally, I would rather use a serial monitor program like PuTTY, or even the built-in Arduino Serial Monitor.