As often with Mac, it is easier than you think:
- In list view Up and Down arrows will move up respectively down in list.
- Left and Right arrows will close respectively open a folder in the list, as it was viewed last time.
- In combination with Option, Left and Right arrows will collapse respectively expand selected folder.
- If a folder was collapsed with Option + Left arrow, it will open like that if opened with Left arrow (only).
The same goes for entire folder content - the whole hierarchy with all subfolders expands and collapses with the Option key held down. And all subfolder will be collapsed (closed) next time they are viewed.
More: Option + Up and Down arrow will travel to the last respectively the first object in the list view, like Home and End.
Command + Up and Down arrow will travel (open) to parent respectively current folder.
Combination of Option+ Command + Arrow may give some unexpected behaviours, mostly it will be alright, sometimes one key too many will cancel out what you wanted to do.
Selecting many folders (like when doing Command + A and then Arrow) may also give some unexpected behaviours.