As someone who was pretty down on Driveclub and Evolution's continuing failure to get out a PS+ Edition in anything resembling a reasonable time period, but now suddenly owns Driveclub and has been enjoying it so far: I think it's a combination of two things. First, I think there's a general reluctance to let Evolution off the hook for their initial failure (which, let's remember, was pretty massive, even ignoring the PS+ problems). We excoriate other developers for releasing products that remain broken months after release, like Halo: MCC and Assassin's Creed: Unity. I think Driveclub catches extra shit because it was promised as a PS4 launch title, and people get real weird when it comes to console wars.
The second reason I think Driveclub gets hit with so much criticism is, paradoxically, because there's a bunch of GAF players who have followed the game's progress since launch and think it's now a really awesome game. As someone who hasn't been able to play any Driveclub at all until a week ago, it's really hard to tell if the people imploring everyone to give Driveclub a second chance are a) genuinely enthusiastic about a much-improved game, b) genuinely enthusiastic about their Stockholm Syndrome for a game they paid full price for that took at least a month to get to proper working order, or c) console war brigade member.
Throw in the bitterness about not being able to see for yourself without paying for a game that, remember, was broken at launch and lacking a PS+ version that might have allowed them to looksee, and the additional comments about not getting the full Driveclub experience unless you shell out for the Season Pass (aka "wait you want me to pay EVEN MORE MONEY for a potentially busted game?") and you have a perfect storm.
I think some people need to get over themselves re: their enduring hatred for Driveclub, but ultimately the game's poor reputation isn't totally undeserved. Re-examinations like the one from GamesRadar will help with this, and I think that in time, people will recognize Driveclub for the game it is now, rather than the game it failed to be at launch. Getting the PS+ Edition out is a big victory on that front.