I have a totally opposite view. FB at least is an "easy" problem in that it's a free product that's mostly casual use. The end result I see is that FB is massively inconsistent, you can literally see different parts of the FB system having a different view on a moderately heavily commented post. Comments will pop in and out of existence on a given device, and different people will have wildly different views for up to a few minutes. If accuracy mattered FB would be just awful.