To talk about reviewing for a second...
I was listening on the radio to people and experts arguing back and forth about the new sound of Linkin Park, and not just whether or not they liked it, but whether or not the band who changed several genres of music had a right to change things up now when so many loved the old, familiar noise.
And I remembered a similar conversation that happened when Anne Rice began writing on religion. And when J.K. Rowling wrote adult fiction. (But not so much when the Red Hot Chili Peppers kept changing...maybe we expected that evolution since they'd done that with every album??)
The truth is no artist has any obligation to do the things you like, or do them repeatedly.
And, who the heck wants art like that, anyway? The on-demand-because-it-sells isn't ever going to be authentic. Or innovative enough to get us to love it like we loved the past things.
I find people get very set, and very emotional, over nostalgia. And that is part of what dictates to how we react to the new, so it's important to keep in mind that things change, and they have a right to.
Also, when reviewing, try to keep in mind what the target audience is and whether or not you fall into that. When you dislike something, bring the detailed reasons to the table so that you can figure out who this would better fit, and why. That, to me, is why we are reviewers. We're helping people discover the new things that would suit them.
If you find yourself too eager to tear something someone else has created apart, I'm not sure you should be in the realm of critiquing or reviewing. I don't think you belong here.
It helps to have been on the other side of whatever art form you are reviewing, but I think just careful consideration of "was this actually meant for me?" and "who would be looking for this right now" works.
You're allowed to dislike whatever you want.
You totally are.
But the end goal of sharing your thoughts as a critic or reviewer should be something more altruistic than knocking someone down or needing a creator to stick to the familiar for personal taste preferences. The world doesn't need more "gatekeepers". We need more new. More fearless.