Misinfo is often driven by political actors, at home & abroad

This EU example illustrates how uncomfortable authorities (like platforms) are in addressing that

Pointing fingers at shadowy groups is one thing. China or US President something else entirely https://nyti.ms/2ztUcKD 

Authorities and platforms can take on shadowy groups with no legitimacy, and also operations from various authoritian countries, whether puffed-up petrostates or not.

But great powers? Presidents of great powers? Major domestic political groups (and sometimes media)? Not so much

This aspect of misinfo debate is not about facts and being "arbiters of truth" but about politics and being "arbiters of legitimacy"

Defacto, however reluctantly, authorities and platforms seem to accept some misinfo as legitimate

(State broadcaster licenced in UK, for example)

I am not comfortable with this, but it may be the least bad option. Some may want authorities and platforms to crack down on everything false, misleading and potentially harmful, but think of consequences if they did - geopolitically, but most fundamentally in domestic politics.

That's also why it is so crucial to have a pluralist response. Not expect a few big institutions to solve everything. But many diverse independent news media, fact-checkers, civil society groups etc (Who need $ and access to data.)