Is it true that german people are too strict

Oh kansasgirl, aren't you patting your county on the back a bit too much here ;-) ?
Certainly America has had its role to play, but I think mainly the more relaxed attitude of the younger generation is due to the fact that we have been travelling a lot more, that it is more common to spend time living or studying in other countries and generally conming in contact with people and cultures outside our own circle of friends or our family, be it abroad or just in other places within Germany. In fact, a lot of Germans are quite fanatical about not appearing German in a very German way, if you get me ;-) A few of them do find their balance and their peace with their native country at some stage, though.
I find it quite hard talking about THE Germans, which is normal, I guess, when you don't have the outside perspective. But I do think it very much depends on the social circle you move in and how much of the world people in that social circle have seen (and I don't mean ticking off counties on a cruise ship).
"Strict" is a harsh word in my eyes, but maybe it seems like that when you look at us from the outside.
There are certainly topics about which a lot of Germans can be unyielding (bear in mid, I am talking from my perspective, being an expat with a well-travelled, studied circle of friends):
Top of the list, as ever, WW2 and the Nazis: Germans who pretend to their British/Irish etc friends to see the funny side are doing just that, they pretend so as not to appear German i.e. lacking humour. It's beaten into us, you surely won't beat it out of us again.
Of course, there's them who think that we should stop feeling guilty and, much worse, them that think that all wasn't bad back then. Which leads to the rest of us feeling responsible and in the defensive all over again.

Recycling and sorting your rubbish. Just do it.

Kehrwoche (your turn to clean the stairs or sidewalk of your house/appartment block). No personal experience, but I hear that that's something feuds have broken out over.

I'm sure there are loads more, but I should really be getting back to work ;-)

And cubie, you are 100% right! Friendships take a while, but when you are there, you very often have friends for life. Patience is the key. And once you know someone who introduces you to their friends, you will have it fairly easy. It#s tougher if you are on your own.