I find it interesting that Germany came up a few times - since I am German.
I am quite torn whether I find it authentic or not.
The buildings I think are a very good representation of Southern Germany. In that I think it does a very good job. But it totally leaves out Northern Germany. So it only is authentic for a part of a country with very distince regional cultures.
And then it lost a huge part of its authenticity with the introduction of the Karamell Küche as those treats being sold there really have only one thing to do with Germany: the sponsor is a German company. But actually Werther's Original are more or less the only caramel candy you can find here. There is a lot of candy which I think would represent Germany very well, but certainly not caramel!
I still think they ought to have a real German bakery there instead with cakes, other baked goods, German sandwiches etc. I am sure it would be a huge hit and it would be authentic!
This is true for several of the World Showcase countries. The UK pavilion focuses mostly on England, and not Scotland, Wales, or Northern Ireland to the same degree. Italy focuses mostly on Venice, even though Venice is arguably the "least Italian" of the Italian provinces (in that it was the most independent and culturally unique when it joined the Italian Republic - even today the city
still has its own language). France, of course, represents Paris alone.
I think what is worth noting about the World Showcase pavilions is that they don't necessarily strive for completely perfect depictions of the countries they represent. They sort of pick some of the most iconic elements of each country, regardless of where they're located or how truly prevalent they are - Japanese pagodas, Mayan pyramids (only in the Yucatan), Bavarian German architecture (only in the south), American colonial city halls (how many cities actually have these? Anyone besides Philadelphia?).
That said, it's worth noting that all of the pavilions are accurate to a degree, in that all of the elements represented in the pavilion are indigenous to that country - but like was said above, it just depends how far you're willing to look in that country to find it. Any visitor to Berlin, or anywhere else in northern Germany, will gladly attest (as I will) that you won't find anything like the German pavilion up there. But there are some towns in Bavaria where the pavilion is pretty dead-on. The average visitor to Japan who spends his entire stay in Tokyo would probably tell you that Japan looks nothing like the Japanese pavilion - but I imagine that there are still plenty of more rural, traditional places in Japan that look just like the pavilion. Much of Marrakesh looks just like the Morocco pavilion, but Casablanca sure doesn't. Every pavilion is, paradoxically, both very accurate and a spectacular failure at capturing the country involved. Weird, huh?