Uses reanimated 2 to collapse comments via reanimated-collapsible-helpers, react-native-svg for the line drawing and FlatList.
Code and typings are rough and maybe ugly, for sure it can be improved. It's just an MVP to get it working. If you have suggestions or improvements feel free to Pull Request.
CollapsibleView was inspired by Eliav2/react-native-collapsible-view
reanimated-collabsiple-headers is patched to support some extra props, changes are in patches folder
Supports 2 level of nesting like major social apps.
The struggle to built it was real...
Demo: