I'm not sure this is proven, the autopsies are done of people with sever cases and may not apply to everyone else. It would be interesting to see autopsy results of people that had the virus but died of something unrelated.
It might not be proven yet, but at least that's what happened to people who survived SARS[1]:
> Bruce England was a paramedic on duty in Toronto during the early days of the Sars outbreak and, having attended a patient with a chest infection, found himself falling ill.
> For him, and many others affected by the Sars outbreak in Toronto, the effects of that experience are still being felt today. Ten years on Bruce still experiences weakness and difficulty with his breathing.
> "I had Sars. It's left a lasting impact on me and my life. So did I survive it? Maybe not, it's still there for me," he says.
It's increasingly looking like COVID-19 is not going to be contained, and if it passes like a flu with more casualties, that's something we can recover from, but if it's gonna leave millions with permanent respiratory damage, then we're going to be feeling the effect for decades.