For more than a decade Canon and Nikon (united called as CaNikon) has been the first choice for the professional photographers. While these two were leading the camera market the sudden rise of the mirrorless cameras packed with improvements to the sensors diminished the CaNikon market. Companies like Sony and Fuji are now leading the mirrorless trend.
Jason Lanier, in the given video states the 10 main reasons for which the photographers now have switched to the companies like Sony and Fuji eliminating Canon and Nikon.
Jason, in his video has deeply discussed (with explanation) about all the 10 reasons, however some of the points are those which we have heard earlier like the small body of mirrorless cameras, innovative pace sensors etc.
Some points mentioned by Jason are the sure reason for debate, but Jason very calmly and brilliantly explains all his points with justifying examples and reason as to why he prefers Sony mirrorless over CaNikon.