Indeed, they can not know quantitatively lifetime risk of COVID-19 after 24 months of observation. But we do know from clinical experience that COVID-19 is damaging a lot of people in very severe ways. I was also quoting data on long COVID that indicate that a lot of people (10% and more) suffer long COVID after 3 and even 6 months.

We also have some data on SARS survivors [0]. The SARS virus is closely related to SARS-CoV-2, but it is a lot more severe.

> Dr. Paula Gardner, a psychologist at St. John’s Rehab in Toronto, has been documenting the health of survivors, post-SARS.

> “They’re still, after 10 years, experiencing problems. Issues such as fatigue, muscle and joint pain, shortness of breath and some newly developing problems such as neuropathy, numbness in the feet and hands,” she said.

We have also experience with the general chronic fatigue syndrome that seems to be related to infectious diseases: https://en.wikipedia.org/wiki/Chronic_fatigue_syndrome#Viral...

[0] https://globalnews.ca/news/404562/sars-10-years-later-how-ar...