That's mainly because, in China, region-based criticism is considered very, very rude.
people don't talk about this in public even though they do have opinions
> I couldn't even get people to tell me some negative stereotypes
it's kinda like you're asking people to tell you some negative stereotypes of colored people
In Europe stereotypes are not limited to nationality, you have them about one specific part of a country (e.g. scots are stereotypically miserly in UK lore, as are people from Genoa in Italy).
Heck we have stereotypes about people from different areas in a single city :)
I think just till relatively recently people didn't travel too far from their hometowns/villages. So there weren't strong stereotypes about people that were effectively far away
Identity is kind of two-tiered. There is a national identity which is strongly tied to history and literature and more "sophisticated" things - and then there is a local identity tied to dialect, food and historically stuff like local opera, music etc.
You're typically not in any way interacting with other local cultures other than the one in your vicinity (other than ethnic minorities - for which there are stereotypes a bit)
Anyway, I could be wrong. Would be curious to hear from someone who grew up in the environment
That seems usually true in densely populated areas that attract people from all over; e.g., most people in NY or LA don't care where you're from; it doesn't even register as something to question.
It's the people in the less dense areas that object (to people they've seldom encountered). They are the ones that much more often object to immigrants or certain ethnic groups. People from less dense areas are the ones who want 'crackdowns' on urban crime - that is, in a community they don't live in. People in the cities vote for liberals overwhelmingly.