The graphics suck primarily due to the fact that the engine SE used does not accommodate realtime streaming of data. Everything is zoned and is not seamless. So in order to give FFXIV the illusion of "good graphics", SE just increased the polygon count of everything and then copy-pasted it into zones with obvious seams and partitions. Basically FFXIV is a few high quality items copy-and-pasted over and over.

Meanwhile other games don't have to compromise on graphical integrity as much purely because the engines they built their games with have gameworld straming technology.