Since most of the comments seem to just restate the conclusion of the article, I'll go ahead and post it:

  > What on earth is going on?
  >
  > Well, my board is based around an ESP32-S3. This has native USB support - and the serial connection is running over the USB connection.
  >
  > We don’t have a USB-to-serial converter on the board.
  >
  > There is no UART.
  >
  > Which means there’s no actual baud rate (this is not strictly true, it is possible to find out what the baud rate was set to - but that’s for another day).