The only way to understand our Brazil policy is to admit there is no single Brazil policy. You have different power centers in the administration pushing different priorities — some want Brazil’s rare earths as a China hedge, which (probably?) requires a good relationship with Lula. Others want a fellow traveler back in charge of Latin America’s biggest country, hence the efforts to favor the Bolsonaros. In the middle you have multiple bureaucratic processes with their own timetable and inertia (like the 301 decision last night), and processes where the politics plays a role (see timing of the FTO designation). And lobbyists.
Trump has his hands around some of this, but not all — because it’s Brazil after all, nobody understands it very well and there are so many other priorities. The ultimate effect is of a White House that is pressing the accelerator and brakes at the same time. Brazil’s only comfort, and this is actually a very crucial point, is that this is happening in several other bilateral relationships as well (See Mexico, India, etc etc)