Lots of issues combined to make some players annoyed.
The underwhelmingness of the whole CQ thing itself. It's 1 style out of 4 promised ones. There's only 1 object that the avatar interacts with (the sofa). The lighting on it seems a bit funny. Spend 10 minutes, and you've seen everything that it offers.
The performance of CQ. It makes graphics cards sweat. Even when it doesn't, it adds to docking time, which if you're in and out all the time (doing in-space activities) is inconvenient.
The interface differences. Harder to tell which ship it is that you have active now.
Removal of the looking at ship view while docked, if not using CQ for performance reasons.
These things mean that the release is not very inspiring. Ordinarily, people would say "worst expansion ever" and keep playing regardless.
The prices of the NeX items aren't even a real issue. Claiming that was the key issue is rather misleading, I'd think.
Then there were these newsletters and emails that were brought out. They created the impression that CCP were ignoring the problems EVE has, in favour of trying to get players to pay more. This is poking a disgruntled bear with a stick. It didn't help.
And so "worst expansion ever" turned into "outrageous, I'm out of here" and so on.
Now, this statement by CCP/CSM looks to have addressed things, but only time will tell.
As for why people began seeing CCP as "the enemy", then it is previous PR disasters such as alleged dev favouritism, ingame event rigging, the whole "18 months" debacle, and various other things, such as saying one thing and doing another, that have helped create this situation.
Constant drip, drip, drip of things, rather than a single event.
They've lost some trust, and will need to do a lot better to regain it.