No, it will not. A professional portrait photographer has deep experience in posing, for starts, and knows how to make someone look natural while enhancing their natural assets. Professionals also know some of the more important aspects of lighting that are not well understood by amateurs.
For example, someone with a very wide face (relatively speaking) should be lit with the key light a little bit further to one side to de-emphasize the width of the face, and enhance the natural contour. Someone with a more narrow face should be lit with the key light placed closer to the camera so that the face appears a little more full.
Someone with dark hair shot against a darker background benefits from a hair light or rimlight to create separation between the hair and the background, while someone who is bald should not be shot with a hairlight, because their scalp will reflect the hairlight creating a hot spot. Now if you shoot a couple and the woman has dark hair, but the man is bald, you need to feather the hairlight to allow for separation between the background and her hair, while restricting the light so that no hot spot is created on top of the man's head.
Also, if you shoot two people who have very different complexions, the one with the lighter complexion needs to be on the side away from the key light, in order to balance somewhat the lighting for the two people, and you may need to use a barndoor to feather the light to capture a more natural looking balance in the final image.
And there is a lot more that a professional would know that will enhance the portrait image, including film to subject distance as it relates to perspective, how to create specular highlights in the eyes, what fill ratios to use, how to light the background appropriately, how to create high key images, in-camera vignettes, and the list goes on. No prosumer camera even scratches the surface of these issues, and that list is nowhere near exhaustive.
On top of all of that, the professional has the instinct and reactions necessary to capture great expressions, and stays on top of the current imaging styles and trends.
Having said all of that, you can take great portraits with a good camera with a little knowledge and some practice.