In reply to Trangia:
I see little change.
Pensioners - the country they are gains their money. Many when ill return the UK too, it's win win. Often people are entitled to healthcare because they apply for permanent residency based on having the funds to support themselves, not because of an EU right. The medical passport thing E111(is it still that?) is for short trips, holidays etc.. and isn't valid if you are permanently residing in another country, 180 days or more is often the rule.
Workers - the UK doesn't export many unskilled workers, it's the educated talent that heads abroad as that is what is missing in the respective country they head to. In or out of the EU does not change the demand for the work. Different parts of the process could become easier or harder, double taxation rules are blessing, but often also a curse etc.. So it's likely to be 6 and 2 threes for workers.