I have two 8K displays.
But even on built in displays, Chrome will output 8K youtube videos and play perfectly smooth at 60fps on my SurfaceBook2 (15" i7 1TB model with 6GB GTX1060) and neither the 13" macbook pro (quad core, 16GB, touchbar, 1TB) or the 15" (six core, 32GB 1TB) one will without constant pausing. Odd isn't it?