Another note: I live in Cambodia, where many French people live, and nearly none of them speak the local language, and a very decent amount of them don’t even speak English. Worse yet, the older generation is still hung up in the idea that it’s better for the locals to learn French than English or Chinese.
This is really a very French thing, and you don’t see the same behavior in eg Germany or Italy.
(I’m originally from The Netherlands)
My German is very poor, I used to somewhat understand what was spoken to me (if simple language was used), and to speak is short, basic sentences with shortage of vocabulary. This is just to provide some context - I never actually tried to learn German.
So I was trying to use English as often as possible. A lot of people - and I mean persons like clerks, salespersons, not random passers-by - either straight-up ignored me, or issuing comments like "Du solltest Sprachen lernen".
On the other hand, I never had similar experience when I was speaking broken French in France (or Marocco).
Please note that I don't want to bash Germans or to defend French. But it all depends on who you encounter - but these encounters might on some level shape your opinion on the whole nation no matter of you want it or not
FWIW, I only ever experienced the discussed issue (locals who clearly understand English but refuse to acknowledge me or respond in their language) in France. I really suspect it's specific to french speakers. They uniquely feel that their language was lingua franca and lost the status to English.
I am trying to understand the situation you were in, because I read that a lot and I cannot imagine why such rudeness.
Which... is certainly understandable! I'm sure she sees a lot of tourism and tourists. But for a neurotic person, being singled out as someone holding up the line by someone who is ostensibly there to help things move faster, because I didn't know a language that I expressly said I didn't know and apologized for, was quite jarring. Up until that point, every single person I met with talked to me like I had a second head that they were generally aware of but didn't care about while they tried to be as polite as possible about not bringing it up. It was a kind of clipped politeness that I have been told is just "german". Nobody cares to be friendly, everyone just wants to exchange only the information needed and, while they do so, they would be as happy and pleasant as a person could be. But as soon as the information had been exchanged, they were right back to bewildered disinterest ("why are you still talking to me? we've finished.", while smiling and nodding).
Anyway, whatever it was that she was trying to tell me, the message never got through. When I answered "no" to her question, she just moved me on through. So maybe she was trying to be polite and I showed my ass or something. Or maybe she was just trying to make a joke and then moved past it when there was no way to make me get it. Whatever the case, I left with the distinct feeling that the author described about that French street. "some people here, sometimes, are going to be very uncharitable about your lack of cultural integration. beware of that." Which, on the one hand is pretty obvious; people are just people all over. But on the other hand, it's probably something most cultures would aspire to minimize.
I'm myself native french speaker and do hate the French attitude on language. It's extremely patronizing and do not benefit anyone