The Remain campaigners may have exaggerated for effect. However, the gist of their predictions - financial turmoil, serious devaluation of sterling (it fell 18% against the US dollar), international business being diverted elsewhere, increasing unemployment and yet more cuts to vital and already hard-pressed public services, are still the probable shape of things to come.
The Brexit brigade, on the other hand, lied blatantly. They knew there wouldn't be any more money for the UK government to spend, quite the opposite, and they knew that the Tory right-wingers driving the campaign don't think we should have an NHS, or indeed any other form of publicly-funded health service; they certainly wouldn't be putting £350 million a week extra into it.
(For those who say that the bus advert that mentioned saving £350 million a week and increasing NHS funding was just a suggestion. Actually, Boris Johnson spoke during the campaign
in front of a message which explicitly promised an extra £350 million a week for the NHS after we leave the EU.)
Mendacity from both sides during the campaign, but an order of magnitude more from the Brexiters.