https://publishing.cdlib.org/ucpressebooks/data/13030/tf/ft0...
Basically, until the 19th century, between 25-35 % of people lived to be 60 or more. In the 20th century, this grew rapidly up to 90 per cent.
80 y.o.-s would be very rare even in the 19th century, while now about half of the population lives to be eighty.
Note that this is the Modern Age. In the Middle Ages, survival would have been worse. A more primitive agriculture, less developed long distance trade and fewer staple foods (no potatoes etc. in Europe prior to the Columbian exchange) would result in frequent famines that took the infirm first.
Things would be yet worse in the Early Middle Ages, the period of frequent nomadic incursions and warfare in most of Europe. At least the High Middle Ages were relatively peaceful compared to the period before.