Why not as a backup strategy? I had my desktop harddrive fail and while I had some local backups but the cloud backup restored me to almost the minute of the failure. The only downside to cloud backup is the slow restore process.
If you use BackBlaze, they offer multiple options to restore data quicker if you're willing to shell out more money, including AWS or sending you a physical drive with your data on it, albeit the latter is kinda expensive, but if you have a ton of data and need it ASAP, is probably worth the cost.
I recently lost a 16TB drive for the second time in 6 months and my local backups were out of date by a couple months, meaning I needed to restore ~200GB of data. Aside from the web interface file explorer window being cramped (and support telling me to basically go fuck myself after suggesting that), I was able to make ZIP files from recently changed data and use their downloader tool which IMHO is a piece of crap and probably designed by some intern, but at least the download speed was fairly fast, even in Europe, in contrast to upload speeds capped at around 250 KB/s (though thankfully support multiple threads).
Data theft is another one. Encryption might help, but you have no reasonable way of knowing if the encryption is secure.