Any historian or theorist or really anyone who pretends to be neutral and not have a bias is either an ignorant fool who doesn't understand the position from which they are speaking, or they're lying to you by trying to sell the idea that their ideological position is natural and neutral. Even when you present "Just the facts" you have to curate your sources and decide which sources you consider legitimate, what parts of those sources you present, and what context you present them in. It's bias all the way down.