Or, at least, it can be good and is often not only unavoidable but desirable. It just has to be handled correctly.
When discussing issues of "metagaming" I think sometimes people lose sight of the fact that playing role playing games is always, to some degree, about the metagame. Regardless of how hard any particular player tries to avoid it - and I don't see why anyone would - it's still there. It kind of comes with the territory and the reality is that you are a human being portraying a character in a game. At the end of the day, every decision is a player decision no matter how much the player wants to wrap it in "character decision" wrapping paper and put a bow on it.
In the scope of Fate Core, it definitely requires a little more "meta" thought than many other games, at least from the perspective that some of the rules the player is engaging (namely, Fate Points and aspects) aren't directly tied to the character's attributes, abilities, etc. Yet a lot of the complaints I hear about this are tied to a play style that I honestly can't figure out why anybody would engage. In essence, that the players only ever engage the aspects and Fate Points at a purely mechanical level, apparently void of the context that they are being used in. They apparently place them front and center of what the game is about, instead of...well, what the game is actually about. When I see this, I begin to wonder, "Is that actually how they are playing it? Instructions are just being issued with absolutely nothing hooking in to what is going on within the game, with the GM and players just pulling things out of their collective asses with only regard for the mechanical benefits and not what actually makes sense?" Because, even if that's not how they're playing the game, it's the way that most people I've seen who complain describe it.
For me, the flow of any roleplaying game has always been about what makes sense, what would follow from doing this or having that event happen. The system has always been slaved to the imaginary space in our heads, not the other way around. Fate's no different. So in the case of just engaging aspects at a mechanical level and pushing the "Fate point economy" to the forefront of the game, yes it does strike me as "bad" metagaming. I can see why anyone would be put off by it. I'm put off by it - regardless of what game we're talking about. It's detrimental to the game and the story. And to be clear, when I say "story" I am talking about (to use +Robert Hanz's words) "the stuff that the characters do, and how the world changes and reacts" rather than "the preplanned story the GM wants to tell". To me, while it is jarring to hear someone say, "I make a Fight roll" instead of "I punch the guy in his face" - it's not nearly as bad as only ever saying, "I invoke aspect X to get a +2".
Part of the reason for this is because aspects naturally flow with the language of what is happening within the game. To me, they demand to be used as seamlessly as possible. Their influence on the game is about what the characters are actually doing with them, and not how they can be manipulated from a mechanical perspective to do things. From that perspective, that's the good kind of metagaming.