I think the tag is fine. In fact I think removing it or otherwise prohibiting its use runs directly counter to the current stated topic of the site. The Help Center explicitly lists "game industry (careers, trends, technology, etc)" as a valid topic.
Just because we haven't seen any questions in the tag recently that we also consider on-topic for other reasons does not mean the tag is, itself, an issue. And removing it would imply a larger discussion about whether or not the help center needs to be revised.
I can certainly envision a future, although I don't necessary endorse or decry it, where we relax certain other existing guidelines to permit discussion of career history or advice.
I do think it needs a excerpt and wiki though. I have tentatively seeded the tag excerpt as follows:
Career refers to the progression, over time, of one's chosen profession. Questions using this tag should be related to such topics, but note that opinion-oriented discussions, such as solicitations for career advice are off-topic. See the full tag wiki for more details.
And the wiki as:
While questions concerning the game industry, including topics related to one's career, are broadly considered on-topic here, many career-related questions tend concern career advice, which can be heavily opinion-based and subject to extensive discussion and are thus off-topic by their nature.
Depending on your specific question, you may be able to find the assistance you need on another StackExchange site, in our chat room, or a discussion forum such as GDNet.
I believe this adequately covers the current de facto state of the tag. If anybody has suggestions for how it could be improved (and cannot improve it themselves due a lack of reputation), please comment here.