My experiences with my body agree with your claim. Clitoral orgasms are easier and more frequently had than vaginal orgasms. For my body, I have vaginal orgasms only in a certain sex position (from behind) and this is more of a G-spot orgasm than a vaginal orgasm, if not completely a G-spot orgasm.
For my body, there’s simply nothing in my vagina that would be pleasurable to cause an orgasm, apart from the G-spot. In fact, a large penis or toy, if it hits my cervix, causes a lot of pain. The most sensitive and pleasurable area of my vagina is the first inch where there are a lot of nerve endings, which are best stimulated directly (finger, tongue, small toy) versus with a penis (which tends to spread things out and creates a different pleasurable feeling than direct stimulation). The clitoris is very similar both in design (nerve endings) and function (direct stimulation). Of course, everything ultimately feels good, it’s just good in a different way. It’s like a buffet, too much of one thing is not really good, a bit of everything is the best approach for a fun night in my mind.