I am starting to find it essential
We can all have different favourites, different views and so on, and still get along, but one or two people love to provoke, be abusive and personal. It's because it is easy to talk big behind a computer, and also the school holidays (no offence to the people at school who are perfectly reasonable and intelligent here!)
People can differ without being aggressive and abusive, or even offensive. Now I have no hesitation in using "ignore" as there are some people it is best to ignore. I did not want to use it, as I like to see what people have to say, but if it is ignorant spouting and reasoning does not work, what can you do?
Having said all that, I think I've only used it 3 times, and two of those I switched it off again.