A number of years ago, they stopped recommending and teaching tourniquets because they were concerned about people losing limbs unnecessarily if tourniquets were to be applied unnecessarily.
However, then the Boston Marathon bombing occurred and the California nightclub shooting and they realized that they had made a tragic mistake because a lot of people lost their lives when they could have been saved.
So now, tourniquets are once again recommended and taught.
JFC, the answer to your question is literally the first sentence of the article. It would have taken you less time to read it then to post your question.