I encountered the mentioned issue at hand as shown below:
Regarding feedback about my current Mac experience, I would appreciate the heads up to install Python before installing 3DCoat itself, either in the requirements page, or in a installation guide shown just after downloading the software.
However, having a un-versioned external dependency like this could lead to more issues down the road (major Python updates with breaking API changes, different Python versions, broken installations, etc), so having a versioned Python interpreter bundled inside 3DCoat would be a much better option.