Well, our experience differs in this case I guess. There are some vibrant parts of youth culture in Germany (in Berlin, etc), but for the most part it is work + weekend binges. There is a coldness one cannot really explain, except if you have leaved in "warmer" societies.
I've heard from people living there that Sweden/Denmark etc are even worse in this aspect.
My experience of Denmark has been that it's a vibrant, diverse, interesting society with some tremendously smart government policies, a lot of tolerance, and some really cool stuff going on, from great filmmaking to a massive Live-Action Roleplaying scene.
Doesn't every young person find the idea of work to be cold? I have lived in Germany and found the people and the society vibrant, friendly, and very warm. They are aggressively pursuing new areas of technological expansion, for me the most exciting being solar and wind power, and they have a very important role as the economic center of the EU. The fact that people there are thoughtful and careful and seek to match their life to their plans and stated goals does not make them cold.
I've heard from people living there that Sweden/Denmark etc are even worse in this aspect.