There will always be a need to run legacy code. For example Dynare (http://www.dynare.org/) is written in Matlab and has established itself as a standard tool for solving and estimating a certain type of macroeconomic model. The authors have been careful to ensure that it works with Octave as well, which I appreciate as someone working in an institution with a limited budget. I teach my own students Python, but as people entering the profession at this point, they should be able to use Dynare as well.