Bias isn’t evil: it’s human.
Humans tell a story with their own particular words, ideas, and emotions. They flavor it with uniqueness. They’re products of their own time, generation, geographical location, and communities. Unlike a dictionary or thesaurus, humans make the story interesting.
The problem isn’t bias: it’s the damage to that bias can do when it masquerades as historical truth.
When people manipulate facts to intentionally mislead or influence someone who doesn’t know the whole picture, it becomes something sinister.
Something manipulative.
When a historian does it, it’s an abomination.

Knowing about the past, in context, chronologically—and reading a wide variety of historians with different perspectives—helps protect against manipulative bias. Rejecting propaganda (even if it espouses ideas with which you agree), acknowledging the points of those with whom you disagree, and trying hard to understand the big picture without flavoring it to your advantage—THESE are skills every person should have.
They are what makes historical literacy commonplace among the people.
Without historical literacy, we will always be subject to the whims of historians who have an axe to grind…and we won’t even know it.