1. It could cause a political backlash
2. It could upset China and undermine research collaborations
3. It could provide validation to Trump and Republicans who touted the theory
But in fact, the journalist's only legitimate question is "is it true?" The consequences of reporting on it are not their concern.
There was a time when journalists thought that way, or at least made a show of it. That time might have been a few brief decades, but it was there.