Here's 4.5 hours of content from various experts:

https://www.youtube.com/watch?v=278vwGkFXRM

There's many more of these types of videos by the NIH and other large groups too.

There are also reviews here: https://www.nature.com/articles/s41579-022-00846-2

Short answer is...we somewhat have hypotheses around the cause. We don't know much about the lasting damage yet.

Many folks who have long covid do not have any organ damage from acute infection. But the big question is if a persistent infection causes damage over the duration.