Here’s the same chart for 2019: https://cs.phncdn.com/insights-static/wp-content/uploads/201...
1. Japanese
2. Hentai
3. Lesbian
4. Milf
5. Korean
6. Asian
1. Japanese
2. Hentai
3. Lesbian
4. Milf
5. Korean
6. Asian
Honestly, JP porn is unwatchable. Squeaky sounds, just quite "unique" as they say. It's the porn you'd watch if you want to quit watching porn.
Bulgaria and Spain are in a class of their own with "Mature".
[1]https://www.joyscribe.com/pornhub-has-revealed-what-everyone...