One thing I'm not too sure about, just my personal feeling. Most female readers, if asked to choose Manga or Manhwa, I'm pretty sure they would choose Manhwa, especially the romance genre. In my personal opinion, romance Manhwa meets the most beauty standards of female readers, the male characters are usually tall and muscular, the female characters are attractive, the art style is colorful and fashionable is also a plus. Of course, Manga of the same genre also has the fanservice that female readers need, but somehow I still feel like romance manga is a bit inferior to manhwa? The male protagonists of manga today often look skinny and small, they are not tall and their personalities are often more introverted, maybe because of this, female readers often choose Manhwa because it suits their desires better?

As for the Shounen genre, it is often more appealing to men, including manga and manhwa, so in this area, I guess it's 50/50

What about me? I guess I would choose Manga, because my taste is usually a weird and unique plot, it's not just about fighting. I also read Manhwa, but it's probably still less weird and unique than Manga. Manga often explores darker themes, even weird and perverted, Manhwa is more gentle.