We should try to follow recommendations from health professionals to the best of our ability.
However if I followed every doctor's recommendation, I would just be taking care of my health every waking hour. I would be very healthy and fit, but I wouldn't have the time to actually enjoy my life.
I don't think humans are categorically stupid. I think they have individual goals, and therefore can't just blindly follow all recommendations. They don't have a trusted administrator input setting, and that's a good thing.
Instead, they need to judge and assess instructions on an ongoing basis. This can be a messy process, but there's no better alternative in a world where you receive instructions from other flawed humans with agendas that differ from your own.