Breja: There wouldn't be a backlash at all, we just wouldn't care at all and would stop watching by now :P Still, I think that when judging Discovery as a whole it's not unfair to criticise the way it treats canon, and it's not just some obsessive fan behaviour. After all, the creators of the show made the decision to make it a prequel and to involve classic characters. They could have set it after Nemesis (last movie in the classic timeline), made the Klingons a new race (the name is all they share anyway) and they'd be scott free.
Still, I think you're way too hang up on the whole "Trek purists" idea. The majority of key criticism against Discovery is not a matter of the canon, but the faults of the writing and characters, and some technical issues. Like I said early on in this thread, some of my favourite Trek novels don't fit the canon well or at all. But I easily ignore it, because they're just such good, well written stories.
Thing is, it might not be the case here but every other post in AVClub for example is about how this isn't "real trek," but the reasoning is generally stuff like "The captain isn't a paragon of valor and good morals," "It's not an ensemble show," "The show shows too many people breaking too many laws, starting with having a rebel for a protagonist," "The show is too dark, in all other series spaceships are lit while here it looks like electricity is too expensive," "I don't like this serialized storytelling, where are my one-off, episodic episodes?" and so on. None of those complaints address the writing itself, but nit-pick on it by comparing it to a show from a bygone era.
I would rather read you guys complain about the Klingon not making sense (they're my least favorite part of the show indeed, not because they don't fit with some lore but because guys be speaking in riddles 90% of the time) or some of the characters going seemingly entirely off-character (blonde science guy suddenly deciding to rebel when in the previous episodes he seemed to be a stuck-up bitch with a penchant for following the rules,) but most of what I read out there isn't that. Most of the criticism I've read from comments is simply nitpicking, and the reviews I've read while far from stellar across the board aren't generally bad either.
Tizzysawr: Far too often fans of the original thing both demand that more things be done with the franchise and then proceed to hate everything anyone does because it's not the original - heck, it happened just last year with the Muppets, for example. It's very, very difficult to tape a new entry into a very old, beloved series and keep the fans happy.
Breja: It's not that hard- the recent two Muppet movies were great.
I loved them, particularly the second one, but I believe they bombed in box office. And then the show bombed in ratings because a split audience wanted different things and seems to hate everything that isn't that.
For full disclosure I loved both the films (well not the first one) and the series. But I'm a weird one like that :P