Everyone is responding based on knowing that the patent troll's claim of patent violation is probably bogus. But the question is over whether the FTC even has jurisdiction over claims of that type. Whether the claim is bogus doesn't come into effect at that stage--you can't say "the FTC can stop the patent troll's lawsuits because their claim is bad", since whether the claim is bad is something that gets decided in the lawsuit (or in the agreement to avoid the lawsuit).
Here's an analogy where the claim is not bad. The police accidentally blow up your house looking for marijuana. Your lawyer tells you that even with the drug war the way it is, a lawsuit is reasonable. So you tell the police "pay for for the damage caused by blowing up my house, or I take you to court". However, at this point the government steps in and says "you are charging people money to blow up your house. By selling the service of letting people blow up your house, you are violating the zoning laws, permit laws, and a whole bunch of other laws related to running businesses. If you try to charge anyone for blowing up houses, including the police, we will put you in jail."
Should they be able to say that? Of course not. There's a difference between selling someone something as a business and "selling" someone something when you are asking them to pay to cover damages. While we may informally say "the patent troll's business is lawsuits", as far as their legal claims go, they're just sitting on the porch and someone else damaged them, and they're only asking anyone to buy a license because that's how you pay for the damages.
I'm not a lawyer so I don't know if that argument will ultimately win in court, but they at least have a legitimate point.