It's going to take 2-3 years before the UK is out of the EU, that is in no way simple. The referendum was only called after decades of political squabbling over

It's going to take 2-3 years before the UK is out of the EU, that is in no way simple. The referendum was only called after decades of political squabbling over the issue and Cameron was extremely confident in putting the question to rest. You are zooming in on one night and ignoring everything that has happened before and what is to happen after.