If people with presuppositions about the past would interpret results and change their beliefs to fit the science, then what explains Creationists?
What does confirmation bias have to do with our science? The reason most of our scientists in our age are atheists is because they were either formerly religious, or the believers who could've beeen in our science field decided that they have the answers instead.
We still have plenty of objects to observe the past with: Stars, fossils, old documents, etc. Bringing about how unobservable the past is would be more of a history topic, rather than a science topic. (We can't minimize terms utilized for a study to mere nerd words.)
Those who recognize their presuppositions as faith are fine, until they start taking the idea that they're right against other people, which is what I see Christians on this site and in positions of power do all the time.