The other 4 are grass being greener.
Unknown future, I would suggest Germany has the most unknown future out of any country right now.
Country leadership, reads like a lot of countries, even a cynical US take.
Too much politics, literally politics.
Architecture, this one is interesting. If you're comparing a postcard or even tourist perspective to a city that you've grown up and lived in your whole life, you will be able to see warts and all what you know but nothing from the city you're comparing it to.
I've had the privilege now of living in a bunch of different cities for enough time to get to know them more than just as a tourist. I would suggest 2 months of time at a minimum to get the vibe, 4-6 to actually know a place and then the more subtle details continue to be noticed / learned of from then on.
A concrete example of something you won't understand about a city until you've lived there is the postal service / how easy it is to recieve things. I had a drivers license circumnavigate the globe after it was returned to sender thanks to the efficency of the Spanish postal service and their ridiculous Franco era hand cart delivery.