Actually, I think it helped that Klink and Schultz were utter fools who always lost to the Americans.
Almost all the actors that portrayed Germans on Hogan’s Heroes were Jewish.
The late Bob Crane once said that Hogan’s Heroes, by that time out of production, was in syndication in 70 countries. Mike Douglas (it was on his show) asked, what about Germany and Japan. Yes, it’s popular in Germany, and in Japan it’s shown as a documentary. ;’)