Hentai is art?

It is absolutely art! Plenty of popular H artists have tens of thousands of followers on Twitter and Pixiv. A lot of hentai and doujin artists take commissions and jobs in the game industry, especially in VNs and gacha games like Fate/Grand Order and Azur Lane. The caliber of art in these games is usually through the roof, and H artists need a lot of artistic skill to create waifus that cultured fans pay good money for (skins, figures, doujins, etc)