Canada has 10 people were square mile and a total population of ~35 million. The United States has 85 people per square mile and a total population of 328 million. A smaller population plays a big role in social programs.
More safety is subjective. Let's ask the First Nations people if they feel safe when so many are murdered by whites every year or denied basic human right of dignity when they're out and about in Canadian cities.
https://www.flare.com/news/racism-in-canada/
https://www.macleans.ca/news/canada/out-of-sight-out-of-mind-2/
Then let's take a look at the top 100 safest towns and cities in the US. The first thing you might notice is the population size.
https://www.safewise.com/safest-cities-america/
Compare to Europe, with 741 million people, twice that of the US, and an average of 188 people per square mile, and you start to see that the averages tend to be higher.
https://www.nationmaster.com/country-info/compare/Europe/United-States/Crime
The mean household income in the US was $72,641 in 2015 and in 2016, it was $70,336 in Canada. Richer middle class doesn't quite make sense when you factor in location. In my area, middle class is 50k a year. In places where cost of living is higher, and the average pay is higher, you'll see significant differences. Middle class in Seattle averages $95,000 a year. Whereas, in San Francisco, it's around $150,000.
And now the funny: They pay less taxes than Americans.
Not really funny nor is it completely true.
https://www.cnbc.com/2017/08/07/canadians-may-pay-more-taxes-than-americans-but-theres-a-catch.html
The size of the population is a factor in overall happiness.
https://www.sciencealert.com/where-you-live-has-a-drastic-effect-on-your-happiness-levels