The ability for people with only Author level access to edit their own articles, ones they have created, is limited to only Articles that are Published, meaning they cannot edit an Article they have created until it becomes Published.
This quirk goes back to a decision or assumption made back in the very first version of Joomla, and maybe Mambo before that, to use the State field, displayed as Status in J4, of article being Published or Unpublished as a pseudo indication of whether it is approved or not approved.
It should/could have been solved with the introduction of Workflow but alas it wasn't.
Specifically to answer your question to work around the above restriction;
The creating of a trail of modifications or revisions per article is already available with the use of History or Versioning which is set by default in J4 and can be turned on in J3 in Content Options. This would be better than creating 'new' articles each time a change is made.
To force any article updated by an Author to become unpublished would need a small Plugin that is executed just before the article is saved to check if someone with Author level access is saving the record and force the State field to be saved as Unpublished. This will mean that any Article edited by an Author will need someone with a higher level of access to 'Approve' the article by making it Published/Approved. This is required due to the permission you are about to change in the next step.
You can allow Authors to edit their own articles, in a Published state or not, by changing the Content Permissions to allow the Authors to Edit State(see image below) which will then allow them to see articles they have created that are in an Unpublished state, however it also means they will be able to see all Articles in an Unpublished State, but not be able to Edit them.
Whether opening up this level of visibility of unpublished articles is an issue for your site is a decision only you can make.
