This seems like a notion lots of people have, but I'm not sure it's true. What is the evidence that online fitness is any more fraught with contradictory advice than, say, online finance, or online self-help?
Also, it's in the interest of the online fitness community to make their advice as complex and complicated as possible as is re-entrenches their "expert" position while the truth tends to be much simpler, as your parent comment alluded to