It says nothing about earning a profit making one a dealer, it says that if the persons primary intent is to earn a profit, they are a dealer. Large difference between those two and it invalidates some of the concerns above.
Here is the exact wording for what would constitute primary intent to earn a profit. All of the below sound like a business, rather than legally buying and selling to improve a personal collection.
Rather than establishing a minimum threshold number of firearms purchased or sold, this rule proposes to clarify that, absent reliable evidence to the contrary, a person will be presumed to be engaged in the business of dealing in firearms when the person:
(1) sells or offers for sale firearms, and also represents to potential buyers or otherwise demonstrates a willingness and ability to purchase and sell additional firearms; (63)
(2) spends more money or its equivalent on purchases of firearms for the purpose of resale than the person's reported taxable gross inome during the applicable period of time; (64)
(3) repetitively purchases for the purpose of resale, or sells or offers for sale firearms—
(A) through straw or sham businesses, (65) or individual straw purchasers or sellers; (66) or
(B) that cannot lawfully be purchased or possessed, including:
(i) stolen firearms (18 U.S.C. 922(j)); (67)
(ii) firearms with the licensee's serial number removed, obliterated, or altered (18 U.S.C. 922(k); 26 U.S.C. 5861(i)); (68)
(iii) firearms imported in violation of law (18 U.S.C. 922(l), 22 U.S.C. 2778, or 26 U.S.C. 5844, 5861(k)); or
(iv) machineguns or other weapons defined as firearms under 26 U.S.C. 5845(a) that were not properly registered in the National Firearms Registration and Transfer Record (18 U.S.C. 922(o); 26 U.S.C. 5861(d)); (69)
(4) repetitively sells or offers for sale firearms—
(A) within 30 days after they were purchased; (70)
(B) that are new, or like new in their original packaging; (71) or
(C) that are of the same or similar kind ( i.e., make/manufacturer, model, caliber/gauge, and action) and type ( i.e., the classification of a firearm as a rifle, shotgun, revolver, pistol, frame, receiver, machinegun, silencer, destructive device, or other firearm); (72)
(5) who, as a former licensee (or responsible person acting on behalf of the former licensee) sells or offers for sale firearms that were in the business inventory of such licensee at the time the license was terminated ( i.e., license revocation, denial of license renewal, license expiration, or surrender of license), and were not transferred to a personal collection in accordance with 18 U.S.C. 923(c) and 27 CFR 478.125a; or
(6) who, as a former licensee (or responsible person acting on behalf of a former licensee) sells or offers for sale firearms that were transferred to a personal collection of such former licensee or responsible person prior to the time the license was terminated, unless: (A) the firearms were received and transferred without any intent to willfully evade the restrictions placed on licensees by chapter 44, title 18, of the United States Code; and (B) one year has passed from the date of transfer to the personal collection.