So taking into considering full range of categories and shooting stills and video, so entire dslr or mirrorless system as a whole, along with selection/prices of lenses, I need to give it up to Nikon D850 for king of all. There are some better values in Canon's lineup of lenses (also taking third party lenses into consideration), but not much so. It's a difficult choice and there are many pros and cons to each system when comparing them all, but D850 definitely wins for best stills shooter, and takes very good full frame UHD video, best low light and dynamic range performance of any camera system currently on the market. Simply can't be beat.
It depends on what you shoot. For me, that's indoor basketball, often at ISO 6400. So I chose the Nikon D750 for it's low light performance and for the AF system. YMMV.
Most of the cameras here are not full frame. And there definitely needs to be some context as to what type of shooting is being considered, and for what budget. This poll is off the rails.
For mid-budget full frame cameras, the 5D MKIII is the best price to product in my honest opinion. I'd definitely love to see that with the EF 24-105mm f/4 L Lens on Massdrop