From a purely personal perspective the FAA does not have the authority to prevent anyone from posting videos anywhere. Nor does anyone else since it's a Constitutional issue. If it's not oriented around national security or restricted/secret level information the government has no cause to interfere with a private individual posting privately owned video. As for letters from the FAA, if they weren't signed by the "Administrator" they are sent as a scare tactic. This has happened before and the FAA quickly backed away from the letters once they were called out on them.
OTOH, and again from a purely personal perspective, we do have a significant problem with people doing some pretty dumb stuff and putting people on the ground at risk when they fly their aircraft obtaining video they intend to use for public dissemination. Some of those people do advertise as aerial professionals, some don't. A lot of them do it for money, some don't. With the release of the Part 107 NPRM it's clear the FAA wants to establish standards for sUAS aerial professionals and once done let people operate commercially. For the moment the only standards available within the law to fly commercially fall under full scale commercial regulations or the Part 333 waiver process, neither of which is suitable for an individual that thinks they are going to make a mark on the industry by posting You Tube quality video. So under the law as it currently stands people flying for compensation or gain are breaking the laws as currently written and the FAA is tasked with enforcing those laws. Perhaps they are just trying to get people's attention by spreading the word? I don't know but if the FAA receives a complaint they are supposed to investigate. That's their job, only how they go about doing it can be questionable. The current federal administration has developed quite a record of ignoring the Constitution, law, and the rights of the people so the FAA may be following some hidden play book based upon upper administrative directives above the FAA.
Again, in my view, a larger condition exists where many, a great many, people don't care about the law or regulations, don't see the law as applicable to them, pay little or no attention to the safety of people or property, and continue to fly in a manner that many would consider careless and reckless. There's also the group, one heavily populated I'm afraid, that don't care about the law, put themselves above the law, and will continue to operate in a manner that puts people at risk after Part 107 is codified. They will not bother applying and testing for a Commercial Operator certificate. Perhaps it's these people's attention the FAA is after? Again. I don't know. One thing is certain, as we move forward with commercial sUAS operations there must be a generally standardized set of operating rules and qualifications. Aerial anarchy with multirotor operations conducted over the heads of the general public is something that just can't be tolerated. To do so virtually assures that in a short time we would all be banned from flying any remotely piloted vehicle at all. There will always be some people that have no regard for rules, regulations, and the safety of others so there will have to be a point in time enforcement of rules is initiated with a few prosecutions to get the point across they have to comply. I try to view this stuff from a broad perspective and not limit to just the M/R, commercial/amateur video generation side of things.
