Simply delete the user account and create the following problem.
1. The document they made goes to the "Former employee" name and the categorization of these older documents becomes a nightmare. There are lots of documents (over the past 15 years) that need to be better organized and currently, the process is very painful.
Retaining the user account costs issues
1. The none-user license fee is a waste
2. There may be security implications such as GDPR, for the company to retain non-worker user accounts.
Please help and much appreciated.