The common complications, of those initially hospitalized(note this limits our extrapolation for population), that were observed in Wuhan were ARDS, acute cardiac injury 7.2%, acute kidney injury 3.6% [1]. This is most likely analogous to having a mild heart attack(we need to read the EKG and labs here to elucidate the actual prognosis), which is still concerning because long term prognosis is usually poor. Acute kidney injury usually progresses to chronic kidney injury.
On top of both of these you're more than correct that lung function will likely decrease. This virus kills lung tissues and although we have cells that are there to heal lungs, SARS-CoV-2 tissue tropism is highest for these cells (ACE2 receptors on type II pneumocytes).
Dr. Facui is one of the most respected scientists in the medical field. He's either in the top ten or right around the top ten of the most referenced. He is the reason why HIV has killed only ~50 million people. I'm building his credibility because he has stated that he hopes we're over reacting to this [2-3].
1)https://pubmed.ncbi.nlm.nih.gov/32031570/
2) https://thehill.com/homenews/sunday-talk-shows/487639-fauci-...
3) https://www.axios.com/fauci-coronavirus-overreaction-decc88f...
