Well let's start with Dave - if any of the claims that economageddon were to be believed, they were undermined by his previously stayed position that the UK could do quite well outside the EU. Which time was he lying?
I'm loathed to defend Cameron because he undoubtedly bears a great deal of responsibility for the screw-up, but if I recall, he said that long-term Britain could prosper either in the EU or out, which is probably true. If he had said that there was no future outside the EU he would
rightly have been accused of scaremongering.
The problems in the short/medium term were predicted quite accurately.