This isn't new. This has been DOJ policy for the last several years. I think they just needed a headline in an election year. Any yes, it has been a murky situation for a long time. It continues to be so.
No.
They are "reinterpreting" the meaning of "being in the business" to effectively cover ALL private party sales, and thus eliminate them.
I don't think so, Tim. "Primarily For profit" is the standard they are using. They declared this early last year as well. That can mean one or any number of sales, so "gun flippers" beware. Private sales for the purpose of improving or disposing of one's own collection are exempt under the law. Where does one start and the other stop? Gray area, of course. The ATF website does give some guidelines, but they are indeed vague.
I agree that the goal of this administration is to eliminate private sales. They just don't have a law that allows them to do it. In the meantime, they push the bounds of existing law as far as possible. Ultimately the courts will decide where the boundary is. Until then, DOJ may, and likely will, harass and intimidate individuals to get compliance.