I finally had the time to try my new breakout. I was putting it off because deep inside I felt there is no chance it can work with the horribly inconsistent schematic and pinout I based this on. And sure enough, it doesn't. I wrote a very simple program to test it:

import board
import digitalio
import time

rst = digitalio.DigitalInOut(board.A4)
rst.switch_to_output(value=False)

cs = digitalio.DigitalInOut(board.A5)
cs.switch_to_output(value=False)

spi = board.SPI()

spi.try_lock()

buffer = bytearray(1)
while True:
    spi.write(b"\x00")
    spi.readinto(buffer)
    print(buffer)
    time.sleep(1)

This should, in theory, print a string of \x0d on the screen. But of course all it prints are \x00. I tried some combinations of pulling down or up various pins that were ambiguous in the schematic that was posted, but I didn't manage to make it return anything else than \x00 or \xff.

I might try some more experimenting with it still, but for now it's a huge disappointment.