What should the tag (cards) be used for?

Question

On the main site, there is a tag called cards. The tag-excerpt says: "Questions about sports trading cards, a common sports collectible."

However, it is not really surprising, that the tag is in practice also used for questions concerning various types of penalty cards (such as yellow card and red card in football). (That is the meaning I would guess for the tag just by its name - without looking at the tag-info. In fact, I have recently edited the tag into one question about yellow cards - only later I have noticed my mistake and removed the tag.)

Questions. Should there be a separate tag for penalty cards (yellow cards, red cards)? Should we keep the current scope of the tag (cards) - only for collectibles?

The tag (cards) was probably created around the time of this discussion: Sports Collectibles - On Topic for Sports SE? (Both on the main site and in chat, the oldest question I was able to find with this tag are from July 2013.)

At the moment, there are three questions tagged cards. One of them about penalty card, two of them about collectibles. There are three more questions about penalty cards where this tag was used by the OP, but it was later removed: https://sports.stackexchange.com/posts/16766/revisions, https://sports.stackexchange.com/posts/13657/revisions, https://sports.stackexchange.com/posts/5112/revisions.

Questions which had this tag in the past can be found using SEDE:

• All posts which had this tag at some point
• Deleted questions which had this tag at the time of deletion
• Posts which had this tag - including the editor who added it
• Posts where the tag was removed - including the editor who removed it

Answer 1

The tag cards alone is ambiguous, and there is no argument to favour one usage above the other.

It should be blacklisted and replaced with unambiguous tags. For example,

• penalty-cards for the green, yellow, red, blue, black, white and other cards used by an official to indicate a penalty during a match

• trading-cards for the cards collected and traded by fans or the general public, and not used in sports themselves

Note that the first tag can have corresponding tags for equivalent equipment in other sports, for example penalty flags as used in motor racing and sailing, while the second can have corresponding tags for equivalent items in memorabilia.