I'm not really sure what to think about all this. For starters, this article seems more fitting to a blog or facebook post, rather than an actual article. Seriously, a hashtag and a dated phrase combined into one?
Although the idea of people throwing a whiny tantrum over LGBT characters merely existing doesn't sound out of the ordinary, I'm a bit more sceptical that this is so clear cut. While I've never been fond of the idea that all characters should be straight and any deviation from this needs to have an entire essay's worth of justifications, it's not so hard to believe that there might be some degree of tokenism going on here. Not that it really matters, since if other comments are to be believed the book itself isn't all that good regardless of sexuality. There are troubling reports of bland characters and an overall air of fan-fiction that hovers over it (an EU book that's basically fan-fiction? Say it ain't so!)
It seems perfectly possible that a great deal of the review bombing is coming from fans of the old EU, if there is any significant review bombing to begin with.
One thing that's worth noting: many of the reviews I just read seem to be aware of the backlash and accusations of tokenism, so many of them seem to feel obligated to at least address the issue, even if it's only to point out that it's a non-issue and not responsible for the negative review. Make of that what you will.
Edit: Okay, I've been reading even more reviews, in fact, I've been exclusively reading the 1 star reviews, and what I've seen does nothing but cast doubt on the accusations of homophobia and review bombing. Only a handful of them have even mentioned it coming across as forced (and none have outright condemned homosexuality, as far as I can see), and even then it's only a footnote in their overall criticism, which seems to mostly be about poor prose, distracting first person present tense, flat characters that lack any development, a boring plot and poor editing to top it all off. So either we have a hoard of rabid homophobes stealthily hiding their bigotry behind a veil of legitimate sounding criticism, or, there is a lot of legitimate criticism to make, and the accusation of homophobic review bombing is completely unfounded.