I don't think he meant it as a German thing.
Trump capitalises words to increase their exposure and importance within a sentence. Goebbels' propaganda machine knew that was effective and did it a lot and Hitler over-emphasised certain words in his speeches too. Trump does the same.
Similarly with the nicknames and other phrases that he repeats ad nauseum, it's all tied into making us remember certain phrases and words and sticking it in our conscious. Goebbels was extremely good at understanding that need.
We know that Trump has read books on Hitler's speeches (despite his protestations that he merely had the books themselves, bullshit Donald as ever) so we know he'll use similar techniques that Hitler and the Nazi Party used to get his message across. For if absolutely nothing else in all of their depravity, they were exceptionally good at propaganda and stoking the fire when they needed to.