Even if you don't have personal financial information stored on your Apple device, the question is whether or not you care if someone else can "break in" to view the information you have backed up to iCloud from your iPhone, iPad, or Apple computer. While you may think it doesn't matter if a hacker sees your photos, iMessages, emails and documents, unfortunately it could all be used for identity theft. Would you care if that happened? I hope so.
From a NY Times Wirecutter article: "The fact that iCloud backups haven’t offered the option of end-to-end encryption until now has long been a point of controversy. iCloud backups of the Messages app were of particular concern because Apple could still hand over certain types of data within the backups to law enforcement. In particular, although conversations in Messages (along with other more personal data types, like the data stored in the Health app) were end-to-end encrypted, backups of those conversations were not. That meant police could subpoena those backups and gain access to texts. A couple of years ago, rumors suggested that Apple had dropped a plan to encrypt backups after the FBI complained about it. But now that the feature is here, everyone should turn it on. Here’s why.
Encryption is a mathematical process that jumbles data in a way that makes it unreadable without a key. End-to-end encryption ensures that only you control that key. This protection allows for private communication between a sender and a receiver—in this case, you’re both—such that third parties can’t access the data. Once you enable Advanced Data Protection, not even Apple will have the key to decrypt your data—and therefore it will have no way to help you regain access if you lose it. End-to-end encryption is common in secure messaging apps like Signal, as well as in software that stores sensitive data, such as password managers.
Many people enable iCloud backups because their iPhone bothers them repeatedly to do so, and perhaps they haven’t thought through the implications. Prior to today, storing a complete backup of your device, including your private photos and files, on a server—where someone other than you has access to it—has meant entering a data-privacy minefield. Someone gaining access to that account, through a data breach or by other means, would have access to anything stored there. And the problem hasn’t been limited to iCloud: Startlingly few cloud storage companies, in fact, offer end-to-end encryption.
But now, if you own one or more Apple devices, you can now make sure that your backups, photo libraries, and iCloud Drive file are end-to-end encrypted."
Apple has a somewhat technical article on "Advanced Data Protection". Apple also provides instructions for "How to turn on Advanced Data Protection for iCloud".