This tendency of people nowadays to focus on tone and other irrelevant characteristics of an argument (as it is made) is dumb.
Wordplay is another, and there is plenty of it in this HN thread.
Boy that Einstein fellow's paper sure had a gruff tone I'm sticking with Newton!
Science uses a watered down but more ~practical form of epistemology, for example equating the knowledge of scientists with all of reality (There is no evidence [that I know of]). Some disciplines (military) use special language to circumvent this problem, at least sometimes.
There is what is true, and then there is the human experience of it, and scientists like most other humans mix the two up regularly. Doing otherwise is "pedantic", and is strongly culturally discouraged.
I'm not sure how tone would be irrelevant; similar to what a sibling commenter said, tone conveys quite a bit of information. It seems unwise or "dumb" to ignore that, because we're still humans talking to each other, even if it's bits over a wire, and we're working together in good faith to learn and solve problems, aren't we?
And yes a posited fact is also known as a claim.