I noticed no one has tag badges yet on UX. I'm curious why not as I'm sure there's a very good reason for it. Is it because we just don't have enough questions/answers/activity to satisfy the requirements for them? If so, is there a way to find out what we need to do to start earning them (eg. how far off are we, might we need to organise our tags better, etc)?
Did you miss the part about "minimum of 20 answers on the tag to be considered"? It looks like you're one question away from getting a bronze badge for forms.
The fact that no badges have been awarded yet makes me wonder whether we tend to choose too narrowly focused tags, and should think more about what fields of expertise a question needs when tagging (e.g., information-architecture, accessibilty, psychology).
Your answer is right in the post that you linked to with the tag rules. The second bullet point is already going to be a problem:
A tag must appear on a minimum of 100 questions to be considered for tag badges.
We've only got 3 tags that meet that requirement right now.
And if you look at the requirements for just a bronze tag badge:
100 total score (sum of upvotes - sum of downvotes)
only non-wiki / non-deleted answers count
minimum of 20 answers on the tag to be considered
That's sum of votes, not sum of points from votes. That means that someone needs at least 100 upvotes in the tag to even be considered for the badge. I think you might be the only one to be getting close to (or past) that.
After that, you need to have at least 20 answers on a tag. The most you have is 19 - for forms. Since that's one of the three tags with > 100 questions, once you answer one more question with that tag, you should get it.