Grace Note has already talked about this extensively, here, here, and here, and possibly elsewhere as well. In short, I agree with him. Tagging is harder on Gaming simply because we have such a larger pool to generate tags from; every individual game deserves a tag of its own!
The problem with the stance of "Meta Tags are BS, eliminate them all", is that it tends to lead to questions being tagged with only the game, and nothing else. If every question only has a single tag, what's the point of having a tag system anyway?
The true benefit of having a tag system, is because of the associations it can establish. If you're looking for advice on TF2 weapons, you search [tf2] and [weapons]. If you want to know how to get all the trophies on Deus Ex:HR, you search [Deus-Ex-Human-Revolution] and [Achievements].
I totally agree that this makes things like my bronze achievements badge meaningless -- but that's a quirk of the tag system, not an issue of a bad tag. Am I an expert on "achievements"? It's a ridiculous concept, I'll admit, but, again, that's not indicative that we should ax the "achievements" tag because of it.
Meta-tags cannot always stand on their own -- but at the same time, they very rarely should be used alone in the first place. Their use is that they help filter both questions and answers, and removing them because they're being used at all is a foolish way to look at it.
I'm going to quote Grace Note here, because I think this is still our best choice when it comes to what we should strive for:
Ultimately, the basic tag rules that I most often use, and which I
encourage, are the following. I do admit to having broken the platform
on a few occasions when it came to a platform exclusive game.
- Tag the game, if you're asking about a specific game.
- Tag the aspects of the game which you are asking about, if possible
(boss-fights, multiplayer, plot, etc.).
- Tag the platform if your question is specifically about one
platform, or about one platform's exclusive features for a game.
- Tag the genre if your question is specifically about that genre.
- Try to avoid tags that are ambiguous (many of us work on
disambiguating various tags).