TV Stereotypes about exaggerated Canadian accents not withstanding, to me Canadian English sounds identical to standard U.S English. I can't tell English speaking Canadians from Americans with neutral accents unless the former actually identify themselves as such.
Why did the Canadian accent remain so close to the standard U.S accent, given how many very distinctive regional accents (Southern, Texas, Midwestern, Boston, NY/NJ, etc...) developed in the U.S that are very different from the neutral accent? Shouldn't have English speakers' accent in Canada diverged in a similar way as those regional examples I mentioned?