Currently the ESP32-S2 port does not support displayio ParallelBus, giving an error:
NotImplementedError: ParallelBus not yet supported

https://github.com/adafruit/circuitpython/blob/main/ports/esp32s2/common-hal/displayio/ParallelBus.c

Comparing the atmel-samd and nrf ports, it seems most of the required updates are in the ParallelBus constructor.

Use of the ParallelBus for displays will be useful in an PyPortal-like device (currently the fastest display speed in the line of Adafruit products). The ESP32-S2 datasheet indicates it has parallel display support of 8/16/24 bit transfers.

-snip-

3.4.3 LCD Interface

The LCD interface supports 8-bit serial RGB, 8080 and 6800 modes. It is implemented using the hardware resources of SPI2. The LCD interface can also support 8/16/24-bit parallel interface (8080), implemented using the hardware resources of I2S.

-/snip-

I think this fits in the long term tasks for whenever new hardware comes along.