Have you noticed that, when it comes to the local church these days, nobody seems to be happy? The millennials whining about the Church from the outside are about as bad as the boomers, builders, busters, and now GenXers whining about it from the inside. Every generation seems upset for one reason or another.
Sorry, I know "whining" isn't a particularly kosher thing to say as a pastor, but let's call a spade a spade. And this needs to be said.

Our BS meters are pretty sensitive.
And there really are churches that are trying to attract our generation based on weird ideas about what we want. Some churches think it’s a particular style of music or a brand of coffee or a style of dress, and while it might help us feel more at home in the long-run, our BS meters go off when you’ve chosen to attract us with gourmet coffee but not friendliness, when you play our music but don’t even try to learn our names, when you look almost like us but just … aren’t. I often hear from others in my generation how they don’t like megachurches, because those churches don’t feel authentic enough - they’re too polished, too pristine … they feel “too fake” to us. It might be that we associate modern music with those televangelists, but it might also be that we have this inkling that the Church is supposed to be different - more gritty, more raw, more involved in the world with the purpose of transformation rather than imitation.

all
the
time.
In my generation - the one that grew up with autotune and photoshop and clickbait and lying televangelists - authenticity feels like it should be something slightly less polished. Not TOO unpolished, mind you (because that would be boring), but just slightly unpolished enough that a few flaws slip through … a few unresolved dissonances or a little cellulite, or even a pastor who has a bad day and is willing to admit it. Those things have a “true” vibe to them because we too can’t sing perfectly or have the perfect body … we too fight with our loved ones on occasion. Our generation wants to identify with the flaws of others because those flaws are common ground and it tells us that we're not trying to be sold a product.

Spirituality instead of religion and all that.
But authenticity tends to look different from generation to generation. We forget that it’s not inauthentic to be polished or pristine or excellent, that it’s not inauthentic to play modern music written by Christians (even the fluff played on KLove), nor is it necessarily inauthentic to be a large church or to have a good smile or to be a polished speaker. In fact, I suspect that we GenYers secretly value those things, but because we’re so used to seeing them, we assume that “real” HAS to look different from our everyday reality where everyone is trying to sell us something.
We want unpolished, and we also want exceptional.
The truth is, “authenticity” has lost its meaning in pop culture from over-use and has taken on more of a "filler" sort of role to sell a brand - any brand. It can mean anything you want it to, thus leaving you justified in your critique and yet strangely not responsible for making anything better. I often wonder if "it's not authentic enough" is the passive-aggressive excuse used when what's going on doesn't match our preferences because it sounds super-spiritual without actually being something we can verify and thus enables the “victim’s” sense of self-righteousness. Some of us, having bought into the lie of individualism, may be simply looking for an excuse to write off the institutional Church, despite the fact that our spiritual lives would be dead without regular gatherings.
Accusations of inauthenticity often seem to be a faux-humble way of saying “I don’t like it.”
Make no mistake, every generation does it. This just happens to be our way.

Being truly authentic is always a risk, and on this journey of transformation, we will get hurt. Sometimes it will be the church that hurts us; I can personally vouch for this reality (I have stories, and I guarantee you almost every pastor with more than a year under her or his belt will tell you the same thing). True transformation of a community or even a church will involve pain. That might not sound good, but it's a part of what it means for the world to be in the midst of reconciliation. "Think of yourself with sober judgment," says Paul, an act that carries with it inevitable discomfort, even anguish with what we'll find.
But don't forget: God is at work. Furthermore, God would not be at work if God thought there was nothing worth redeeming.
So if you tell me there’s something horribly wrong with the local church - especially if you say that it's not authentic enough - I’m going to want to know what you’re doing to help make it better. The Church is a necessary, fundamental part of God's plan for redeeming the world, and so you don’t get to "whine and walk," as it were, because that helps nobody, least of all you.
If you’re going to point out a problem, you must then by necessity be part of the solution.