In the old days Nikon cameras could be knocked around and still be relied on to work. Canon were more fragile. But Olympus made the most rugged cameras of them all! I remember a professional mountain photographer dropping his OM1 down a rock face, perhaps 30 feet. He went down for it and it still worked, so he finished his shoot.
Don't know whether any of today's cameras are as rugged, but although I have no intention of dropping my Canon 5D I suspect it'd fare pretty well.
A semi-professional underwater photographer friend of mine decided after many years to change from Canon to Nikon, only a couple of years ago. He gave as his reason that Canon charged silly money for some of their more exotic lenses, whereas Nikon were far more reasonable.
He must have been convinced, as the change cost him an enormous amount of money - at least $60k.
I still have some old German rangefinder cameras - Zeiss, Voigtlander and Leica. I recall a public statement issued by Zeiss (West Germany) many years ago, maybe 25 but I may be way out, that "their traditional way of hand-making lenses had at last been overtaken by a Japanese manufacturer, who had perfected machinery capable of making lenses not just much more cheaply, but also of better quality".
I seem to remember the Japanese manufacturer was Nikon, but it may have been Hoya or someone else. I'm pretty sure it wasn't Canon.