Don't throw away your old servers! Your old servers are excellent data sponges for off-site backups in your own private cloud!
Instead of manually swapping USB drives or tapes, we have converted most of our customers' old Windows servers into off-site cloud backup servers!
They can now back up your virtual machines daily and automatically at a fraction of the cost of using the public cloud, USB drives, or tapes.
To do the conversion. we simply would add a couple of large-capacity drives 8TB or greater and install open-source software to do the backup and data compression.
Typically, a 10-year-old Windows server we set up for our customers can back up at least 1TB worth of virtual machines per day over the Internet, and store between 90 days' worth of daily backups, and 12 months' worth of archives.
We recommend that, even if you have moved your primary servers to the Amazon, Google, or MS cloud, you should still use your own servers for local daily backups and monthly archives.
As an insurance IT policy, you should download all your VMs daily. Doing so will reduce the risk of the public cloud service providers going down, being attacked by hackers., or denial of your service for violation of their ToS.
Full disclosure: ECL resells public cloud backup services by Amazon, Google, and Microsoft. ECL also offers its own competing private cloud backup services locally in Canada.