Maybe. Maybe not.
It takes time to become a good controller, so don't expect the be a wiz at that sim. However, it is easier than the real thing. Notice the pause button? Plus you can slow everyone on inital contact to 160 then speed em up with out a problem, among other things. If you try and handle it like you would in real life it is a fairly hard sim for how simple it is.
Not to mention slowing someone to 160 then rechecking and raising their speed restriction is going to set off the pilot's larm bells. Anything under 170 for a jet and you're basically raising the white flag 99% of the time.
Keep in mind every few clicks of your mouse takes the place of dialouge between you and the pilot. Like clearing the aircraft for the approach is actually...
Oh lets not foget the 10 frequencies you're monititoring. I promise you the readback will come right as a student pilot is stepping on the jet you just cleared. They'll finally stop talking as the jet is on a 3 mile final.
Example for PDX: "Delta twenty-two twenty, you are six miles from TOLOC, turn right heading two five zero, maintain two thousand til established on the localizer, cleared for the ILS runaway two eight right apporoach, contact tower over TOLOC."
Pretty good phraseology there, nice work.
Which after a while flows out of you smoothly with out doing much thinking. Amost like clicking a mouse
But, throw in visual seperation between two aircraft landing on parallel runways and you can be sayin a lot more before they are cleared.