The installer Install BlackBerry 10 Desktop Software.app inside the BlackBerry 10 Desktop Software_1.2.0.58_B60.dmg image for BlackBerry Link/Blend does not start the installer under macOS Sierra. Running the binary inside the installer .app directly gives the following error:

/Volumes/BlackBerry\ 10\ Desktop\ Software/Install\ BlackBerry\ 10\ Desktop\ Software.app/Contents/MacOS/Install\ BlackBerry\ 10\ Desktop\ Software ; exit;/Library/LaunchAgents/com.rim.BBLaunchAgent.plist: Could not find specified service/Library/LaunchDaemons/com.rim.BBDaemon.plist: Could not find specified service

However under the Resources folder of the package content there is BlackBerry Blend.pkg installer. Running it brings up the installer window and the installation succeeds and everything works fine ever after.