$1:
Writing for the court majority, Chief Justice John Roberts agreed that the law was substantially too broad and therefore invalid under the First Amendment.
What the fear was, was that the law would ban depictions, documentaries, and etc. of (in particular) bullfighting. While I am not a supporter of such a thing, it is legal in Mexico and other Latin countries and it is an entrenched part of their culture. With some 45 million Hispanics in the USA this law is saying that they can't buy videos of something that is perfectly legal in their home country.
The law, as written, needed to be struck down.
Now Congress can try again.