This question already has an answer here:
This is now the second time I see an answer here where my first impulse as German was "What the heck?"
The first answer was How to tell a colleague to take care how he looks. It has many answers which I personally find totally off the mark with a high number of upvotes where people admitted that they neither belong or have experience with German culture (doctordonna said that the is the Canadian perspective). What even more irritated me was that people tried to discuss with me from their own cultural viewpoint.
The second answer is How to ask cashier out of date where the most upvoted answer from Tinkeringbell is extremely aggressive and, more serious, shows a lack of cultural knowledge, the answer is as stated not acceptable. According to her profile she is from the Netherlands, but Germans and Dutch people are different (And in fact I am bit surprised because she reacts quite unusual for a Dutch person).
I will tell the reasons and cultural differences in an own answer, but I really want to ask the obvious question:
Shouldn't we people remind that for a good answer for a cultural specific question it is an obvious precondition that the answering person belongs to the culture or has extensive experience with it (spouse, long stay)?
Shouldn't we give some kind of indication in the answer what our actual experience is?
The thing is there are many other Germans with a totally different viewpoint, they may disagree with me, even in different directions (!). But our answers together give a quite good picture what we all find not ok and where there is some interpretation room.
I must also say that distance is also not a good indicator for similarity of cultures. I can drive in less of one hour over to Denmark, but Danish people are in general much more reserved and cautious than Germans.
What in my opinion is not ok is giving advice from cultural ignorance, it brings people in trouble. If such answers are upvoted, many people will see them, hold them for true and likely don't look further down where they may get warned that it the suggested behavior sounds nice, but is culturally not acceptable.
I do not think it needs saying, but this concerns naturally all groups: Italians, Chinese people, Nigerian people, Christians, Jews, LGBT, whatever.