There's no problem with doing crazy things with one button. You just seem to favour the games that make you do only one simple action with one press, or think they take more skill. Like I said, it's all in the spacing, timing, nuances, and such.
Dungeon Fighter Online is a great example. You have plenty of one button press skills that do amazing and flashy things! But the intermediate-advanced combos are very difficult. Why? Because of the things I mentioned.
Spacing is very, VERY important in DFO, you need to adjust your combo for pretty much every instance you get a hit.
Different classes fall faster or slower, so you you need to adjust your timing in air combos, or even do different combos.
Some classes have options to break out of being comboed or something, so you have to keep it in mind and predict when or where they'll use it.
Some classes can leave lingering projectiles and the like on the stage, so you need to adjust your combo yet again.
Just a few of the examples, but it's stuff like this that makes combos satisfying and difficult. The fact that you press buttons in order regardless of what they do to combo is irrelevant, that's not where the satisfaction or difficulty comes from. Every game will have you pressing buttons in order to combo!