Actually no, at least not in WoW during its prime. This is not what the fun of (these kind of) MMOs is about. And thats also why I dont think MMOs and 4E are anywhere close.
In MMOs it is about having a good strategy and executing it, while reacting to dangers (evade attacks). There is no tactics involved. You know beforehand exactly when you want to do what. At least for the boss fights.
For the not boss fights (which are called trash fights), there its more similar to what was previously said, but overall it does not really matter. You will NOT use any cooldowns which matter during trash, because during boss fights you want to have everything ready, because thats the challenge, the other parts is just filler.
MMOs are about perfect execution of your strategy during stress over 100s of turns. RPGs are about improvising and tactical play. Making the best of your 5 turns you normally have using your abilities at the best possible time.
Just som examples:
- The difference between a good Arcane Mage and an average arcane mage was mostly just how good they are at their rythm.
- An arcane mage had to press 1, 1, 1, 2 repeat. Almost the whole fight. After pressing 1 you had to wait for lets say 1 second to be able to press it again. A good arcane mage managed to press 1 after 1.01 seconds. A bad one in average had 1.16 seconds or so.
- As a cooldown reliant class (death knight which only came later is the clearest example so I use that). You would press exactly every 1 second a button. As above you had to make sure to do it exactly every 1 second. Now which button depends on the cooldown, but every players (should) know exactly the priority order of their attacks. You know attack 1 is the most important, followed by attack 2, by attack 3 etc. The cooldowns of attacks was normally exactly X seconds. So a good DK would need to press exactly 1 second after the last press the highest priority attack, which cooldown was up now. No thinking just executing and muscle memory kinda.
- As explained by someone before, there were some abilities with long cooldowns. They had 30 seconds, 2 minute 3 minute or 5 minute. In general you would always use ALL cooldowns you have together, EXACTLY as they are ready again. So you would not think about "is it a good time to use this now?" but you would think "I must use this as soon as the fight starts (some seconds delay to give the tank aggro), and then whenever they come up, this way I might be able to use them 1 more time during the fight).
- Healers are a bit different, but they would often not even really see the fight and mostly just look at life bars, and just tried to heal them as fast as possible after they got damaged: This is how a typical healer screen would look like https://cesspit.net/drupalbackup/storeroom/wow-repository/priestui.jpg
- What made these things "hard" was that you had to move (depending on boss fight) at certain points. As a melee you would need to always stay behind the enemy and move as they move. As a caster you would need to only move when you knew that an attack would be comming to where you are, and then you would try to move the least amount of time possible. (And if you have use a movement ability like a teleport), such that you lose as little time as possible and be able to again press your rotation 1, 1, 1, 2, 1, 1, 1, 2, etc.
- Another big aspect was coordination and having a strategy as a team. You would play with up to 40 people. And you would need to select teammembers accordingly before. And each healer would know exactly who they would need to heal (and were not allowed to do anything else like damage normally). Each tank which enemie(s) to aggro. And damagedealer which target to focus etc. Also the mechanics of the boss would for 99.99% of the people be known beforehand and they would need to watch guides and know when to move. There would be messages (voice text and markes) telling when to move out of an attack.
- Also remember the huge number of buttons you saw in the above image? In actual play you will in 99% of the time only use 5 maybe 7 of your 30-40 buttons. You are optimized to need as phew buttons as possible. 1 button with all cooldowns on them. 3-5 buttons with your best optimized attacks. Sometimes 1-2 "I don't want to die" buttons which are also clear when to use.
WoW is a great example of teamplay, but it is not tactical. You dont improvise, else people will scream at you. You follow order with utmost precision and as efficient as possible.
I agree though, that it is interesting to look for how to do variety, which is a goal in D&D 4E and similar games, but was NOT a goal of WoW and similar MMORPGs. (There the goal was perfect repetition).