Estimates from the literature are that between 5% and 50% of Covid infections lead to long term (> 3 months) symptoms. There must be a lot of recovery if only 3%-5% has lingering symptoms. Did they account for drop-out of the more serious cases?

https://www.cidrap.umn.edu/covid-19/long-covid-may-affect-5-healthcare-workers-hospitals-new-data-suggest