That would be closer to Nirvana fallacy, applied to activism. "People do something good. You criticize them for not doing something better instead." This argument happens all the time. See also The Copenhagen Interpretation of Ethics.

There is a standard solution S0 that almost everyone chooses. Someone chooses a better solution S1. They get attacked for not choosing even better solution S2.

The harmful part is that choosing S1 over S2 is socially punished, while choosing S0 over both S1 and S2 flies under the radar. If the reason for choosing S1 over S2 was that the solution S2 was too complicated or too expensive, we effectively teach people to choose S0 over S1 to avoid the punishment in the future.

(Specifically: S2 = reporting on Lebanon and Paris attacks appropriately; S1 = focusing on Paris; S0 = ignoring both.)