I think the issue is with Canadian companies buying out/merging with numerous American railroads in an attempt to dominate, whereas American Railroads are not allowed to purchase Canadian, or something like that... if it were the case, American railroads probably would be in Canada more than they are now (I think they can only be leased).
It's the political inequalities between the two governments which makes a Canadian takeover intolerable.
I live near Detroit and am not happy with how CN runs things. Grade crossings are in need of repair (most of them) because of lack of maintenance, the trains they do run here are few and usually around 2 miles long, because they don't want to have two shorter trains, rather just one 10,000 ft long one running at 25MPH and blocking crossings for a decent amount of time.
These are my personal dislikes, but here the line they've taken over, and have had for years is the Grand Trunk Western Railroad.
Then there's the other things like them trying to merge with BNSF, but because the gov't here wouldn't allow it, they just bought WC, and several other shorter lines instead... I just don't get it, but I guess I shouldn't have to, there is a bigger issue with the "free enterprise" in how we accept Canadian garbage in our landfills by the truck-load 24/7.