Sorry but what she's saying is 100% true?
I adore France - particularly Paris, I've lived there before and come on, it's well known the French can be really rude. I have encountered a great deal of rude French people, particularly in stores/basically wherever customer service is concerned.
Of course there's a mixture of rude + polite people everywhere, and I have encountered a many great polite French people. But I'm just saying she certainly isn't exaggerating by any means.
I get her bit about the clothes in a shop may seem a little extra, but it's difficult to really convey unless you experience it. Like you really do (quite often) have to pause for a bit between your 'hello' and then your question. It just feels odd and can be a bit of an adjustment.
Also we have to consider the context here, she is discussing the difference between France (which we've established is famous for being rude) and America which couldn't be more of a polar opposite - to the extent where a lot of people can find Americans (in a customer service way) sometimes even a little overbearing with how helpful they try to be. She is just highlighting there is a vast difference between politeness/customer service in the two cultures.
Chill out France