It's not about expressing your opinion. There is difference, when you politely say what you think, and there are facts, and there are some thoughts, but you need to know place and time.

I think it's more disrespectful to others when you do not follow common internet/forum rules, and post before you search, when you start new threads for things that exist. It's like saying that your opinion/post/thread is better than one already made. That they instead of search they easy on start the new topic, that means they appreciate their time more valuable than others.

That's just disrespect and not about opinions...