Comment by GuB-42

The way life expectancy is usually calculated, it shouldn't have an effect. It is calculated is by looking at the mortality rate for each age group, which gives a probability of death for each age, and by simulating people growing up in such conditions, and then taking the average age of death.

By doing so, historical events outside of the study period don't have a major effect. In this study, they deliberately avoided the covid pandemic as it would have caused a significant drop in life expectancy that is not representative of a general trend. Of course, the future is not taken into account either. Despite what the name may suggest, life expectancy is like a snapshot of the studied period (1990-2019 here), not a prediction.