He said, “Sag mal, wie lange wollt ihr bei dem Scheiß bleiben?” He said the problem was that Trump was rambling (this part of the speech was unscripted). Article is in German. Here’s a partial translation by DeepL, tweaked by me:

His interjection should not be interpreted as a political statement. “No, that would be completely wrong. The political content is not the problem,“ says Deja, adding: ”I interpret all the time for people whose political statements I don’t agree with. The problem with Trump was that he suddenly started associating freely or saying the same thing three times in a row. The difficulty when interpreting is following these confusing leaps of thought.” He explains: “If a speaker has organized thoughts, then as soon as the sentence has started, you can roughly guess what will come next. You can keep surfing that wave. But that’s impossible with Trump.”

I believe it, because simultaneous interpreting is really hard, intense work. You have to listen, remember it word for word, understand it, and give an accurate, natural sounding translation pretty much instantly. You have to try to convey the tone, understand cultural differences, and figure out how to say things that just don’t translate well. It’s so much work that interpreters often work in teams so they can relieve each other every 30 minutes or so.