If you literally mean to ask if it is that easy to start an engine by touching some wires together beneath the steering column, then yes it is, if you know the correct wires to touch together, and you can get at them.
If you mean to ask if it is that easy to steal a car, by just casually reaching under the steering column, blindly yanking a handful of what you can grab, quickly producing two or three bare tipped wires, touching them together, and driving away... then no, it is not that easy. Although it is possible to START a car this way, you still face the problem of the steering wheel being locked.
I guess you could steal it by starting it that way, and driving away only in the direction that the wheels are pointed... but your getaway would be rather short I'd imagine.
You can expect that in movies you will not be shown things like everything necessary to easily hotwire a car, or build a bomb, or hack the National Defense Grid, because Hollywood doesn't want to end up being responsible for when people then turn around and use what they learned.