A search here at StackExchange, at Reddit & via Google yields no clear answer. Has anyone found a way to force list view as the default view?
Depending on your version, this setting may be at the new location /io/elementary/files/files/default-viewmode. This changes to the mode of the currently active tab or last tab closed (which will be the end one if you have more than one).
Tabs will restore with the mode they had when the app closed. Default viewmode is used when you press the
+ button to create a new tab or if you create a new tab using
<Ctrl>-T or the
Duplicate tab option.
You might like to monitor this setting with dconf-editor while using Files to see its behaviour.
Ask and I shall receive ... Five minutes later, I found my answer at https://askubuntu.com/questions/134371/how-do-i-set-default-view-to-list-in-nautilus-file-manager