Salaries are very fixed at those companies. You will start at around 50k€ after university, advance to 70-80€ during the next years and will be basically stuck there. The corporations have defined fixed salary levels together with the unions and these don't contain any "super-complex", "in-demand" or "rockstar" levels. It doesn't even matter whether you are doing mechanical engineering, software, or powerpoint engineering. There exist higher salaries, but only for team leads and above - which mostly don't perform technical work anymore.