The problem with just reading the Bible is that there are lots of voices. If you don't think about how to deal with that, you'll pick the one your tradition accepts and just read over the others.
For example, Jesus had both male and female disciples. Female followers were nearly unheard of. Yes, he called the men, but the women were just as close to him, and were more faithful at the end. Paul accepted female leaders, and said that in Christ there is no male or female. There are two possible readings of 1 Tim (since the same Greek word can be wife or woman). But under one, women leaders are prohibited. The traditional reading considers this passage controlling and explains away the others. Everyone makes decisions like that. You have to.
There are also rules for what to do with OT laws. Sure, there's good reason for those rules, but we don't just read OT passages literally. We read them in accordance with Christian understanding. And not all Christians agree. During much of Christian history, Christians took literally the prohibition against charging interest. There are still disagreements about the Sabbath.
There are debates over now some parts of the Bible were intended. E.g. I think Jonah is an obvious satire. Some people think it's history.
Not to mention things that just aren't clear, e.g. whether to baptize infants or abortion. People have convinced themselves that the Bible speaks clearly on both topics, but they're reading their own understanding into the text.
All of these questions have reasonable answers, but if you claim you're not making decisions, you're likely to simply accept whatever you grew up with or heard in your church, without thinking about the interpretation behind them.
Finally, there are parts of the Bible that are just wrong, if interpreted literally. Gen 1 is one of them. We do ourselves no favor by pretending that scientists are engaged in a conspiracy against Christianity.
