Nah, this is more nuanced than that. If I held up a sign that said "Remember, you can find them guilty" that is also factually correct but could be interpreted as trying to influence the jury to that verdict.

That is what this is about. I can see why this could be seen as contempt of court and I can see why this would also be seen as fair part of protest.

I don't think the judge is badly ignorant of the law, but rather in a very difficult position of trying to preside over a fair trial while also dealing with protestor outside court. He got it wrong in this case, but it's not a simple and straight forward good vs evil story.