Animation locks is what differentiates Tera's combat from everything else that's normally compared, not the fact you have to aim at things. Wow had aiming, albeit on a very small amount of abilities, but shit like cone of cold and shadowflame(I think?) and you had pbaes like frost nova and ground targetted aoes like flamestrike(mostly taking mage examples cause it was mostly for the mage). GW2 has soft aiming, you select a target and your shit goes towards the target, but hitting without a target would also work, on most skills, and the shit that was directly targetted could be avoided if it was a projectile of some sort(most were) or even melee attacks. Tera had a bit more aiming, but it also had stuff like lock on stuff. But overall it's not too different in that regard, it's obviously more than wow and a bit more than GW2 but similar to wildstar.
The main difference is in the animation locking. Animation locking gives weight to abilities, other than damage and cooldown. A slow animation needs to be aimed properly or set up with another ability because it can be heavily punished. A short animation does less damage but can be used to poke or in situations where time doesn't allow for a slow ability to be used safely. Some animations can be cancelled by other skills. Some animations involve forced movement meaning you can decide to use those both for damage and positionning at the same time. The combat is similar to fighting games where you don't just press Strong Punch over and over or even spam Hadokens all game because you will get punished by anyone smarter(or in the case of mobs, the fact they can just walk into your hadokens and not stagger or lose much health). This is supported by very tight hitboxes and very small aoes(other than aoes that are purposefully big like zerker whirlwind, which is full of issues like the fact it lasts forever, has a charge time and reduces your movement to shit). Most classes are in fact short range to emphasize the combat system. There's sorc and archer but both have a lot of medium/short range abilities and keeping your distance when you have to stop for spells and don't have 150 CC is obviously not always doable.
On the other hand, you have GW2 and Wildstar, with the "move while doing everything" combat. This is a floaty combat system, that is in many ways similar to the wow old system. You have to aim your shit sure, but that's about the only restrictions you have other than cooldowns. You look at your bar of skills and you always press the strongest skill that is available. There is no reason not to. Some skills do require you to stand still but they're pure "charge up" skills, they do more damage while trading movement, similar to the Tera style combat tradeoff, but they're few and far between and in a game where 90% of the skills can be cast while moving, casting something that doesn't let you move make you an easy target. In PvE that translates into having to move before you're doing channeling every fucking time because the fire is spawned quickly and often since most of the time you can move and fight at the same time. The difficulty layer comes from being able to move in the right spot at the right time, and not using your abilities correctly. Using your abilities correctly is as easy as setting up a mod that shows you the next highest priority ability you will have available, wow style(you know the one if you've played in late BC+ wow).
Regardless though it can be fulfilling and fun to play combat like GW2 or Wildstar and there's some good things about being able to move all the time, but it's in no way similar to Tera's combat.