This is a common misconception. The only reason e.g. Against Malaria has a 'funding gap' is because the EA funds don't want to fill it out of fear of 'crowding out' individual donors which is a sketchy proposition.
This may have been true for some time in the past, but it seems that new funding opportunities/causes have cropped up which are competitive with AMF, so that the EA funds are once again constrained by the overall amount of funding.
