Time to never buy any book from them again. I'm moving on to pirating ebooks and audiobooks. Sorry JRR and Christopher Tolkien (may you rest in peace), but I'm not buying any more of your books because they were published by HarperCollins. And I'm also not buying a lot of other books too.
I really appreciate the sentiment, but sadly: Individual boycots that aren't attached to a concertated campaign sadly don't work. Pirate away, but you can be certain that these publishers don't know that you exist.
Maybe, but I am boycotting all capitalist entities the best I can. If I need something I try to buy used or from worker co-ops or to check it out from a library or pirate it.
I would argue this is actually one of the most effective ways to respond. If enough people do it then the company has to react somehow (by pivoting, etc.). Obviously an organized effort would be better, but the "vote with your money" method isn't anything to ridicule.
Name one instance where that worked when it wasn't connected to a massive public outcry. Do you remember the Call of Duty "boycott"? Ubisoft is still in business, too.
Also, the majority of book buyers don't know or care about this verdict.
Also also: The publishers won't even be able to correlate the "lost" revenue of individual people boycotting with their shitty behavior. It's not "Oh, we sold 1000 less copies of this book than expected, because we fought the archive." It's more: "Our predictions were off by 1000 copies. No idea if that's because of some tangible factor, or just 'noise'."
Encapsulated in that "etc." in my first response is "going out of business". This type of response would be way too difficult to get actual numbers for, but it has worked countless times. Just look at all the businesses that are no longer in business at all, they went out of business because they were no longer earning enough to stay viable.
It doesn't matter if the company connects the loss to a specific action (although it would be nice) since the end result is the same, after enough time.
Lastly, I just don't like the idea of my dollars being used by a company to further an agenda that I don't want to support.