That's the point of civil debates. To discuss and challenge the ideas in order to reach a better understanding. If you're simply going to tell people to "fuck right off" without addressing their concerns it shows a deep lack of understanding of their concerns and only helps to push them further away from your own position.
What advantage do you get from insulting someone? Whilst I don't agree with the original post, I don't want to excuse this behaviour of the reply.
Where was the insult in OP's post?
I only saw OP putting their points across quite peacefully and then out of nowhere