Actually, BI is just a tool to help you makes any analytical assumption or decision making...
I have seen people doing analytical purely based on excel spreadsheet and the company is still growing...
So why do BI is trending these few years? Because instead maintaining hundred / thousands excel spreadsheet, it is simpler and faster to maintain one system (BI System). And of course it comes with fancy chart and animation (though nothing like you seen on film.)
And in the end, the decision is still in your hands. If your thinking is not critical, you are wasting your investment on one expensive system. As i stressed it again, BI just helps you seeing the data in a simpler, more accurate, and faster way.
Heck, they even now can make a BI from social media... You can make people's comment on facebook, twitter's tweet into a fancy chart.