I'm surprised at that too. I'm wondering if maybe she missed the boat on that though. There seemed to be dozens of crap YouTuber books a few years ago. Maybe it was a fad?
Yeah, it's mainly this.
Publishers were eager to crap out YouTuber vanity books a few years ago because it was a relatively new thing and they thought a popular name on a book would be enough to sell it, regardless of quality. Now they've tested the waters, seen that subscriber counts don't translate to guaranteed books sales and they're not likely to make the same mistake again unless it's a mega-huge star.
Fiction is a big gamble for a YouTuber vanity book, and it's pretty much never worked out. Zoella's book was mired in controversy after it was outed as being ghostwritten, Sasha Alsberg had to pair with an established author to write one and the end result was mercilessly roasted online, Christine Riccio's first book was put out through a tiny publisher and was similarly terrible, with most online reviews tearing it to shreds.
Jack got his deal mainly due to timing (it being written/published just before the peak popularity of Studytube died), combined with it being a generic self-help, non-fiction book which is an easier gamble for a publisher than a YA fiction title. But even then, just looks at UnjadedJade's attempt at doing the same 1 year later - she could only get published through a tiny, never-heard-of-them publisher and it sold almost no copies, because the window on getting a book published purely because of your name and follower count has long closed.
Ruby has no chance. She's writing fiction with no talent, long after the peak of her minor fame has gone. She might've been able to land an agent based on her name, but that's the easy part. She's missed the window on getting a vanity book deal and her writing is a known quantity now, too. Publishers only need to Google her to find she already wrote a half-assed book that nobody bought, and that was at the height of her popularity - nobody's buying a YA fiction book with Ruby's name on it. She's handed them a proven test case for how poorly her book will read and sell.
The most she can hope for now is a tiny deal from a no-name publisher who'll slap it on shelves unedited with a cover that looks like it was ripped from Deviantart. But Ruby's set herself up with the entitled expectation that she's going to get Stephen King levels of success and anything less will be like another Oxford rejection for her. She should've stuck with self-publishing.
