Most of the things said about Brexit in both directions were predictions about the future. Many such predictions were obviously nonsense but could be justified

Most of the things said about Brexit in both directions were predictions about the future. Many such predictions were obviously nonsense but could be justified on the grounds that it could happen, or rather, that the speakers believed strongly that the predictions were not nonsense. A sibling post has already highlighted one of the most notorious examples (voting Leave will trigger an immediate and huge recession), which was promoted as totally the consensus and nobody intelligent could possibly disagree with this guaranteed-to-happen-by-experts prediction. But there were many others (£4300 worse off in 15 years or whatever it was). Did the government really believe these predictions? We can't really know if they were intentionally manipulative or earnestly believed. The Turkey case is maybe a bit like that. How likely it is to happen depends a lot on your beliefs about what future EU leadership will do. Recall that Turkey joining has been official policy in the not too distant past. Recall also that the people who ultimately control the EU - men like Juncker - routinely say in public that all borders are bad and that the future of Europe is vast quantities of Islamic immigration, that there is a moral imperative to let that happen in fact. And Turkey is a huge and Islamic country on the border of the EU that wants to join the EU. You don't have to be particularly weird or paranoid to assume that whatever objections may currently exist might go away in future. Or you could say it's evil and manipulative and fake news. Depends entirely on your perspective. There's one difference - the economic prediction was short term and already proven false. Turkey joining the EU was a long term prediction with no particular attached timeline, I think. It's harder to falsify.