Is the C++ API for the BrickPi3 still supported, on Pi4?

I am writing a C++ program for Pi4 to run LEGO motors connected to a BrickPi3. As soon as I instantiate a BrickPi3 I get spi_setup error. This is because the call to open(SPIDEV_FILE_NAME, O_RDWR) returns -1.

I am running the latest image of Raspbian for Robots (buster) for the Pi4, on a Pi4 model B with 4 GB of RAM.

Is the C++ BrickPi3 API supported on Pi4?

[UPDATE] Also the Python API seems to have issues on my Pi4. I am getting:

~> pwd
~> python
Traceback (most recent call last):
  File "", line 17, in <module>
    import brickpi3 # import the BrickPi3 drivers
  File "build/bdist.linux-armv7l/egg/", line 21, in <module>
IOError: [Errno 2] No such file or directory

I have updated the software and firmware, checked that SPI is enabled, but no change.

The update for BrickPi3 software may have actually failed. This time, instead of running it with the desktop icon, I run it with
sudo curl -kL | bash
which stopped with errors:

Package python-wxgtk2.8 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'python-wxgtk2.8' has no installation candidate
E: Unable to locate package wx2.8-i18n
E: Couldn't find any package by glob 'wx2.8-i18n'
E: Couldn't find any package by regex 'wx2.8-i18n'
Installing TroubleShooting
Done with TRoubleshooting
Done installing RFR_Tool

I merged a PR moments ago, addressing this issue.