and another study that seems to demonstrate the opposite. By definition, every study is "incomplete". You must look at a range of literature to get a larger, more accurate perspective.
There is considerable literature on the subject of the anatomy of the clitoris; in a sense this article reiterates what has been known anatomically about the clitoris for well over a decade. Most of us, mean and women alike, know that the clitoris is more than a simple vaginal "capstone". Most of us know that stimulating the clitoris and its deeper structures near the vaginal opening feels good, and can produce orgasm... much of the time, but not always. If we take a simple anatomical/mechanistic approach, it is precisely this "much of the time" fact that reveals a flaw in the article... there must be additional mechanisms beyond the anatomical at work.
There are structures in the vagina, other than the deeper clitoral structures, that are involved in sexual arousal and orgasm. The authors of the article mention contractions of the bulbocavernosus muscle at the entrance of the vagina as the contractions of orgasm. True... but incomplete. We also know that deeper vaginal contractions involving other muscles of the pelvic floor can occur during orgasm. Specifically, cervical "dipping" is a purported biological mechanism for ensuring semen enters the uterus for purposes of procreation.
The article doesn't even scratch the surface of explaining why vaginal lubrication increases when the anterior fornix is stimulated, why baroceptors in the vagina communicate a pleasant feeling of "fullness" when a penis is inserted, why different positions may feel better to one woman than others (given that the penis contacts different vaginal structures in different sexual positions), why the vagina elongates when stimulated and tents at peak arousal, and so on...
So... don't hang your hat on a single article. The body is a complex system consisting of much, much more than structures. It is waaayyy more complex and fascinating than that.