Descriptions here generally aren't updated (unless the dev themselves update them) for changes like this. This game does basically have incest, it's just not "officially" a part of it now. It's only changed, like you say, so it doesn't violate Patreon's rules now. But incest was always meant to be in the game. It's just like the tag for incest. Does a game technically have incest if a patch is required to see it? One could argue no, not technically since the patch isn't "official" on Patreon or something. But I think you get the point. The description wasn't changed because really there is incest in the game; it's just hidden and requires a patch to see it as it was always intended.
In the Intro :
mc : "Julia is
my childhood friend. We grew up together, she was always close.
She was like a big sister to me so I never thought of her as a woman."
mc : "I love her but I have never felt desire for her. And I doubt that it could change."
I did not apply the incest patch and 1 min into the game they are already siblings :
Julia : "After all, I didn't move out of
our parent's house just to have you move in with me!"
mc : "Oh, gee, thanks Julia. I feel so welcome now..."
Julia : "Come on, kiddo, you were never welcomed or even planned, just ask
our parents, they'll tell you that you're here by accident. But since you're here..."
mc : "Uh huh... (Actually, Julia was the accidental one, conceived back when
our parents were wild hippies. I'm the one who was planned after her birth made them mature and settle down. I've tried to tell her that...)"
So if they are still siblings after the changed Intro line, what does the incest patch really do?