Tanking in SWTOR isn't that hard, but it feels unrewarding somehow. As a healer and DPS I can feel my impact more on the flashpoint/Operation, whereas a tank I feel like a damage sponge that does some dps. But is tanking in SWTOR more difficult than tanking in WoW? No, not all. Is healing or dpsing in SWTOR more "fun" than tanking? Contextual, but in my experience, a little bit yes.
Interesting point. My tank is too low level to have a meaningful opinion on end-game stuff, but I do enjoy tanking lower-level flashpoints.
However, I will say that my respect for good tanks went way up when I first started EC. A sloppy Toth/Zorn swap can wipe the group. A smooth and well-executed T/Z swap is a beautiful thing -- like watching dinosaurs dance.