Not every culture has the same standards of politeness. I didn't think it was rude, I think it can be even respectful of their time and intelligence to be concise, plain and direct, as long as you are not literally attacking them.

I mean, the comments under the GPT-5.1 announcement just today were full of people wishing that AI actually responded to them like this.

https://news.ycombinator.com/item?id=45904551