I don't know when giving you a multitude of skills that do the same thing suddenly became the norm, but more complex it is certainly not. It gets to a point where you lose immersion because of those dang buttons. Our guild in EQ2 got together for the final fight of a heritage quest. This involved waves of mobs coming at us which I never actually saw because I was so focused on my buttons. Take a look at these hotbars:

So what I have here are four heals that I use. And the reason for them? Because they each have refresh timers, so I must switch to another heal while the other is refreshing. Now really why not one heal that refreshes right away? Am I more skillful because I know how to use my other heals? The same goes with my cures. I have four cures for various ailments. There is a cure for them all, but it's got a very long refresh so the single versions are better. I won't even go into the other buttons plus the bars you don't see that I keep at the top of my screen.
I've used my mystic here as example, but the same goes for my melee alts. All these damage dealing buttons that do the same thing with varying degrees of damage. I'm playing a button MMO. Press, press, press, keep watching for refresh, press, press.
I especially became more aware of this after sticking my nose back in EQ1. Their recent expansion pack dropped in price and hubby wanted to see what things were like now (but that's another story for later). I logged in my beastlord to see my one lonely hotbar:

Now there is a limited spellbar off to the side with my slow I use at the beginning of the fight and a heal for emergencies. And also there are special abilities on a separate bar I can only use once every few minutes. But for the most part it's attack on and kick. I took her out for a trial run to get a feel for the gameplay again. When things get tough or adds come, you're relying on non-hotbar abilities to get through. The biggest difference I noticed while playing was that I saw everything going on around me because I wasn't having to stare at my bars. I could actually enjoy my environment. What you're really relying on here is your gear and quick responses.
EQ1 may be a bit too extreme as far as limited abilities go in today's market but really I think things have gone overboard in some MMO's. You're getting the same thing disguised with different names and long refreshes so that it "feels" like you're getting more for your buck. I realize not all MMO's are as extreme as EQ2 as far as the volume of abilities go. But I do hope it's not a trend in upcoming MMO's. I'd really like to get back to enjoying the environment around me.