Oh, well, I personally like all kinds of artstyles, although if you'd ask me for my favourites, they'd likely turn out to not be non-anime, but more stylized/unconventional spins on anime art... Like Steins;Gate for example. The point being, I'm a weeb, I like anime-style things and most people that will ever look at a visual novel for more than 5 seconds are either like me or Japanese.
From their very beginnings, Japanese VNs had a pretty strong connections to anime and they are made primarily for Japanese readers, who seem to be pretty conservative with their tastes. Non-JP VNs are made primarily for weebs, often very explicitly copying Japanese media to appeal to Western otaku. While writing about VNs I always advocated for non-JP devs to avoid being copycats, but mostly in the sense of creating their own narratives and experimenting with style. I don't think rejecting anime art is needed that much, the thing you should probably try to avoid is being generic and uninspired, which a lot of VNs (from all sources) are. Plus VNs, no matter who makes them, are currently offering very thin profit margins, sadly making anything more than mild experimentation quite a big risk. You can make a non-anime one, but unless you absolutely nail the presentation, it might very easily appeal to no one – the weebs or JP otakus won't like the departure from what they usually enjoy and the broader audience still won't find your "waifu power point presentation" interesting enough to check out. Thus, I don't think VNs can really free themselves from anime art, or have much reason to do so. They won't get meainstream any time soon, considering they didn't already and the younger generations generally have the attention spans of gerbils.