Also, my personal experience is the opposite. My parents allowed me to walk outside by myself in both big-city Toronto and Brisbane with no problems. Many of my friends can attest to the same...
This is generally true for us inner-city kids throughout the "Anglosphere", however, the problem is that we're simply outnumbered by suburbanites to such a large extent. Thus leading me to believe the overbearing parent is largely a learned behavior brought about primarily through urban design, rather than a cultural trait of English-speaking countries.
As for your comment about Canada being an "Anglo-Saxon" nation, I doubt many Brits in the street would consider the UK "Anglo-Saxon" given the ethnic diversity present in the UK these days, but that doesn't mean it doesn't have Anglo-Saxon roots that have strongly influenced the culture, laws, literature and history of that country. But I digress.
Its not merely a question of ethnic diversity (and even if it were, Anglo-Saxons constitute the majority of the UK's population, which is not the case in the other 4 countries), but that in the case of Canada at least, it has much more than "Anglo-Saxon roots" - it was neither initially settled nor colonized by Britain, merely taken possession of at a later time by them. Which of course has influenced its laws, culture, etc. but again, we could say the same of India, which I certainly wouldn't call an Anglo-Saxon nation.
I only continued this line of discussion because of your fellow Canadian making such a song and dance about the use of a term which, in my mind (as well as others) was perfectly acceptable to use in a bid to score "one-up" on me.
No, its not about you, actually, but rather an inaccurate (and quite chauvinistic and patriarchal) description of 4 countries. Don't know what they teach you in the UK, but its not the only country or people that has played a role in the history and formation of these 4 (particularly Canada & the US).