The ad triggered a series of events that helped my friend.
The doctor, for whatever reason, was not the primary motivation.
just to be clear i don't know your friend or their life or their medical condition or if the drug you saw an ad for treats their condition or if you saw an ad for a drug or if your friend has a medical conditon or if you have a friend at all... and i don't know if every event in a chain of events is necessary to the eventual outcome of that chain of events... and i can't see into the alternate reality wherein you didn't see that ad for a drug, to know your friend would've been fine in the end... and so on.
i'm speaking more generally, saying advertising is superfluous to medicine.
If I wanted that level of care, I expect to pay for a personal physician who only has one patient. Me.
The reality is most of the time my Dr knows more technical info than the patient. But sometimes I know something they don’t. The information asymmetry lasts about 60 seconds before my doctor validates the info against his professional sources.
My doctor is providing a value commiserate with what I pay him.
The role of search
The first gets blasted all over the internet to be shoved in the faces of all and sundry.
The second goes quietly and efficiently to the professionals tasked with helping the individuals in society with problems that may directly benefit from new thing.
The distinction, to me, is obvious.