There are historically lots of things that "seemed obvious" but couldn't hold up under research, which is why we do research. It confirms what you think or maybe it forces you to question what you think. Either way, it is good.
Case and point, there is a rising opinion lately which Trump has promoted that your heart only beats a set, finite number, of beats in a lifetime. Therefore, according to this opposing hypothesis, it makes sense to not perform intense cardiovascular activity throughout your life, because it accelerates your heart hitting that finite limit that it is capable of. This opinion has gained traction in recent years and to some people it "seems obvious" that a faster heartrate might wear it out more quickly, leading to premature death. So to those people, research like this defeats their assumptions and helps them feel more confident about performing exercise because it is research-backed that Cardiovascular Fitness prolongs life.
That's why research is important. Obvious shouldn't stand for anything.