Why should I? (but I do anyway...but define better, half the shit released in the alst 10 years...actual 'games' are shit...much like the modern film industry...I prefer to play 20+ year old games). VN's are just an extension and evolution of comics and Graphic Novels....and yes, I 'play' a lot of Non sexual VN's too...
I would also add on to this (thinking while I had a coffee) that:
Do you really play VN's? Are they really a game? They are more like the old Choose Your Own Adventure/Fantasy Play books, of which I have a large collection which I still read to this day. Grailquest...Lone Wolf...loved them. Again, just an extension of those for a different market and 'AVNs' have sex scenes in them? I don't know about you, but I stopped jerking off to pictures and shitty animated stuff over 40 years ago....maybe they still get you off, I dunno, you do you I guess but again, not why I like VN's.
I also love the art. I've been using Daz/Poser myself for over 20 years....like Comics > VN's....Daz is just an extension of pinup and fantasy art from yesteryear (I still love Vellajo, Royo, Giger and Francis work etc) , which I've also had an interest in for a long ass time. I understand the work, effort, time and skill involved in making good renders...so I appreciate the medium. There are a lot of damn good story-tellers around the VN world. are they good writers also? Most are not no, but they have the story...and this is a perfect medium for them to tell said story that would perhaps not work elsewhere.
So play better 'games'? As said before, like Hollywood, most 'games' out in the last ten plus years are fucking recycled garbage for the idiot masses with no attention spans (much like every itteration of later D%D editions). *shrugs*....obviously I read these for very different reasons to many other people and would suspect, am also older than the majority of people who like this genre medium too.
Disclaimer: That's not to say I don't play some AVN's purely to see how ridiculous and depraved some of the scenes are. They are fun things to read/watch but those are very much the exception.