BornAgain for macOS is distributed through the project’s Homebrew tap, not as a wheel on PyPI.
Install Apple’s Command Line Tools and Homebrew, then add the tap and install BornAgain:
xcode-select --install
brew tap mlz/homebrew https://jugit.fz-juelich.de/mlz/homebrew/
brew install mlz/homebrew/bornagain@25.0
Run bornagain_info after installation for the paths and commands needed to
install the locally produced wheel and access the example scripts. The tap’s
README
contains the maintained step-by-step instructions.