Right? There are any number of benign reasons that that image/footage could have been momentarily displayed. Could have been a promo of the American Military's history fighting in WW2. Could have been a political ad comparing Biden to Hitler or something (distasteful, but still relatively benign).
Like don't get me wrong, the Republican party grows ever closer to a MAGA-themed Nazism part 2, but they aren't that tone def as a whole yet. The absolute least likely reason for that screenshot is that they literally just had a Hitler rally speech in German playing in the background for the ambience. Let's be serious here and shit on the Republicans for the shit they actually do, not for unfortunate/ironic images with no actual context.