Slowing down fake news is a good thing, and nothing is perfect, which was rather my point too. The grandparent poster states that "(facebook) should not be a platform for propaganda", an absolute statement implying that it is desirable to keep _all_ "propaganda" off facebook (it might be, assuming you can define propaganda) and that it is also reasonably possible to do so (a lot less likely).
I take the point about paid ads, but that does not cover all of "propaganda" any more.