1) Facts exist. Often we have an incomplete understanding of facts, and there is something like a working mental model of facts. An educated mind allows for the possibility that the facts are sometimes subject to new information which can sometimes change them. Without these facts, we couldn't make buildings stand up, and they do. They do because we have an understanding of how to make them do so based on facts. Homicide detectives and heart surgeons have a notion of facts based on evidence and very very often they get it right because there are knowable, searchable, demonstrable facts. If you doubt objective reality then imagine sleepwalking in front of a train: your perspective is irrelevant. The train is coming whether you know it or not. 2) Sometimes people are wrong. Sometimes people aren't interested in facts because it conflicts with their agenda. Some people don't want to work to find the truth. That's why proof and evidence are so important. "When did WWI start?" might require years of study to understand the complexities of what touched off that where and provide a nuanced "answer". Hearing different voices on this topic is part of an education, but being able to differentiate credible voices from those who attempt to instrumentalize the past, or worse yet, provide some kind of hard and fast sense of history by omitting important facts, is NOT a good way to educate the populace.

3) Interpretation is also based on what you can back up. I can interpret "There are no aliens in Roswell New Mexico" to mean "There are DEFINITELY aliens in Roswell New Mexico". However, without some kind of proof behind that interpretation see number 1. A bad working model of the territory makes a bad map. Also, the claim that facts are neither interesting nor important is false and dangerous.

4)

You ar missing the point. Facts are not objective because interpretations are not. Man hit by train is not the only interpretation of two clusters of atoms hitting each other.

Death is not the only interpretation of the carbon based structure that is now smeared on to the front of the steel construction

Interpretations don't change conditions; conditions exist regardless of perception or interpretation. At the point where interpretation becomes so obtuse as to try to revise the immutable reality of death (and taxes?), something is wrong. When this kind of relativistic, obtuse, "subjective" argument is brought to bear it is usually driven by a political bias(I.E. "Our" history versus "Their" history.) Certainly interpretation can play a part in communication but more often misinterpreting reality leads to consequences of a nature not interpretable, such as the loss of a work situation. What I mean to say is, the limits of the subjective stretch only so far before playing with them leads to consequences in real life. Play semantic games with a spouse or boss and see how far it goes.