I don't agree. In my opinion, the complete lack of diligence on why his businesses failed four times and the limp dicked retorts to his bullshit about the Muslims celebrating seems more indicative of a media afraid of him-- or perhaps thankful for him-- than one out to get him.
here's the thing, you get into the ins and outs of bankruptcy laws and joe sixpack tunes right out. They don't understand finance and don't care to. This isn't going to be a successful way to attack him even among those that understand finance and pay attention- Trump has hundreds of small businesses set up to do just about everything, and the vast majority are successful. the ones that aren't tend to be casinos in jersey- and atlantic city is in complete shambles due to pennsylvania expanding their gambling operations. Three casinos shut down and went bankrupt last year alone.
As for muslims celebrating, whether they did or not is irrelevant. Trump knows he'll be called out on it, but this is another opportunity to portray the media as having an agenda, and being the tough guy that takes a stand against them. The "liberal media!" strategy NEVER fails to work among the conservative base. Why should they play into that more? it only benefits trump.
Carson's collapse isn't due to anything the media did- Everyone knew he was an intellectual lightweight, but those backing him cared more about things like jesus and morals than understanding foreign policy- until a terror attack reminded them it might kinda sorta be important and they jumped ship to trump who is viewed as being stronger on foreign policy and terrorism than anyone else, and has been for almost as long as he's been running.
Trump is teflon because he doesn't HAVE any weaknesses for his opponents to exploit in the primary. He's smart enough to engage anyone in a debate on any topic, and has already run so far to the right on terrorism and immigration that outflanking him by going even harder right isn't really possible unless you're going to advocate burning muslims alive at the stake.