A lot to unpack here but an excellent question.
Let’s go with you CAN farm out your backups - you still need them of course. With the cloud services (Azure, AWS, GCP, etc.), they have the backup products to keep multiple copies around the world and to do restores.
Let’s take this to a higher level view and assume we’re talking about businesses and not personal files. I think we are conditioned to throw all of our files onto a shared drive because we were raised on file servers. Are all documents equal? Do they contain sensitive data like Personally Identifiable Information? Personal Health Information? Trade Secrets? Credit Card Info? Business Plans? What are their retention policies? Sometimes saving everything forever can become a liability. When you make a local backup, you must be prepared to physically secure the backup, encrypt it, and check it periodically to make sure the media can be restored if needed.
With the cloud, there are many, many more choices for file storage depending on the answers above.
OneDrive for Business is SharePoint under the hood. With SharePoint, you can easily tag documents with sensitivity. In fact, there’s a new product that searches through your documents for sensitive data (Government IDs, Credit Cards, Healthcare information, etc.) and tags it for you. Also with SharePoint:
- Documents can be versioned and restored to a previous version. You know WHO made any changes by version. Online editing is a breeze unlike file shares.
- There is a recycle bin. If you accidentally delete a file, you can recover it for a number of days. After that, it goes to another recycle bin for a total of 3 months and your admin can restore it.
- Documents can be shared within and out of the organization with little involvement from IT (other than policy of course!). Sharing can expire and the sharer knows when and who has opened the document.
- You can prevent a file from being emailed, printed, screenshot, or downloaded (but not protect from photographing the screen…)
- Files can be sync’d locally or pull “on-demand”. Syncing is now incremental so large files sync quicker. (Caution with sync. IF you don’t use On-Demand and you start to run out of local disc and you delete files, you will delete them on SharePoint! It’s recoverable as mentioned above but a PITA nonetheless.)
- Is essentially free with your M365 subscription
For those who can’t live without a file server, it’s the most expensive option and has a few more features than a local file share. Can sync but doesn’t have the other SharePoint features. Still requires IT to setup and maintain security.
Both Microsoft and AWS have very inexpensive blob storage. It can be immutable. It’s optimized for further processing services (Data Lakes, ML, …) It’s not accessible from SMB, a favorite tool of viruses that ravage local networks and leak data. Depending on retrieval speed, it can be very inexpensive. Could be a good candidate for backup up personal files too.