I didn't like the stories to Black & White very much, and even less so B2W2.
When I was younger, I liked it a little more than ordinary Pokemon narratives, which is not a high bar to overcome, but it's still something. It seemed less childish than other games.
Now I think much less of it. Okay, N was somewhat of a grayscale character, and that's a good thing for a good-vs-evil story. The great error, though is trying to justify the ancient Pokemon question of Why is it okay to take what are basically wild animals from their homes and force them to inflict horrible violence upon one another, and why do those animals grow fonder of their captors for forcing them to do that? The answer is plainly that it is not right to torture living creatures in this elaborate system of cruelty and therefore that acknowledging this problem and trying to justify it in a story (and doing a very bad job of justifying it) is only going to accentuate how bad that behavior is.
As simple as Pokemon stories had been up to that point, it still would have been better to adopt that model of simple storytelling than to try to solve a moral issue that is always going to exist as long as Pokemon is Pokemon. Until the gameplay uses only emotionless robots for fighting, it is a ridiculous idea that the moral problem of Pokemon could be solved. Let sleeping dogs lie.
Also, there are little bits with NPCs that irk me. I remember when your male rival hands you some item with no context to the story and no acknowledgement of what's happened recently. I'm sure people will say that's necessary with the way Pokemon works, but I disagree. And then there are characters like, I think, the 5th gym leader? who speaks with a ridiculous Texan accent that is meant to amuse children but is just a depthless caricature to adults.
And Ghetsis! Okay, a lot of the time his dialogue is basically on point with his mission. But every once in a while he says a non sequitur or otherwise out-of-context comment that really reminds you that you're playing a video game, not engaging with a story.
I write this while donning my flame-resistant shield. I know this is a thread about unpopular opinions but like any such thread anywhere, people are going to be reading it and think, "Wow, that is the worst opinion ever, and I must let them know it."