As a grad student I once worked for a scholar on a community archives project that included a timeline of the history of his field. I quickly discovered that his text was almost entirely plagiarized AND that his source (pre-AI!) got a lot of things wrong, including many citations.
One paper I tracked down from the mid-1800s was incorrectly cited in every instance of citation I found thanks to lazy researchers copying one man's mistakes. I, not an expert in that field but merely a person willing to check citations, caught that within minutes of looking.
Plus I also work in an academic library and we absolutely have a group chat to talk about the books we've been reading. I'm no influencer on here, but I do hand sell people on books all the time IRL! If people post about good books on here, that word of mouth does reach outside the platform.
I'm fortunate enough to have disposable income and I want to spend it on books! I'm an easy sell on a good book! I can only do that if I know to look for it because there are so many authors whose work I love that it's easy to overlook someone if no one is talking about their new book.