[patrickk]

There are multiple, mature products in the "enterprise document management" space that work similarly to the product that you describe, available on premises and in the cloud[1]. There's also (smaller, specialised) consulting companies that show how to implement these products into a business. There's some really nice features like robust OCR, meaning after scanning, you can search immediately for document metadata, like invoices numbers- for companies that insist on having paper documents as part of their processes, or crusty old management that refuses to have digital signatures.

The challenge is the same as the main topic of this thread- change management. You have to force employees to manage their documents exclusively within this system rather than dumping everything into shared drives and using Outlook attachments for everything.

[1] One example: https://www.alfresco.com/ecm-software/document-management