Emacs in a terminal misses out on various text properties, on things like client frames (or just multiple frames in general), on images, and on font/size variety. I suppose you may feel like you don’t want to ever touch the mouse for some reason but I think it’s often useful for scrolling, selecting, copying, and pasting. There are also a bunch of keys which can’t be differentiated by a terminal. Finally the gui wastes less space on buffer dividers and the fringe