https://www.realclearpolitics.com/e..._democratic_presidential_nomination-6730.html
It clearly shows on this map of poll averages that a huge dip started about October 2nd. I fluctuated slightly downwards about a day before, which is normal, but it took a huge dip right after the news of him having heart problems came out. There is nothing else that would have caused this dip other than the fact that he was literally in the hospital, because Warrens surge only started scalping Bernie voters after Oct 2nd. So it cannot be attributed to Warrens previous upward trend.
There is also Economist/YouGov polling that show among Dem primary voters that 66% of them think his health is a legitimate issue and 13% arent sure about it. How are you gonna win a primary if you just had a heart problem and that many people are either not sure or sure that your health is a legitimate issue? You are gonna be stuck at your 21% loyal supporters (who clearly arent as loyal as we thought according to the RCP polling average) and you will never be able to convince them that a 78 year old man with a heart issue is healthy enough to be president lol. So no, the media didnt "wite his campaign failing into existence". His future nonexistent campaign prospects come from an honest appraisal of the facts.
Also, how do you even media brainwash people into thinking that a 78 year old with a heart problem would be a bad choice for president? That like saying you can brainwash people into drinking water. Its just something they are going to think by themselves. Its not gonna matter what the media do or dont say.