Ransomware continues to surprise me in different ways. Recently there was an incident where data was not only encrypted, but also copied back to the criminals. In this case, Apple was the target through a supplier with the ransom note saying that without a payment, the data would be auctioned off.
That's crazy. Not only might you have business issues where you can't access data, but now you have the stress of the data possibly being released or sold. While not many of us work in organizations where our data would be worth $50mm, it might be worth a significant amount, especially if the data were customer data. This alone might be a good reason to ensure that you have local data already encrypted without the keys present. At least then the criminals couldn't read your data.
This doesn't help with SQL Server and TDE. In that case, the certificate would be inside the local master database, and if someone could attach it and get access to the master database, they could read your databases. If you have an SMK and a DMK, perhaps this might offer some protection, but I don't think so. This does mean that Always Encrypted might help, unless you have lots of servers or other machines on your network with the certificates, in which case someone might be able to piece together the keys and read data.
Attacks are becoming more numerous and creative. Having backups might have protected you against some ransomware, but not if copies of your files are sent to criminals. Perhaps the access from servers to the outside world needs to be more reigned in. Not much fun for administrators, but this might be the future of protecting systems.
The arms race between sysadmins that protect infrastructure and criminals seems to have taken a leap forward here, and I'm not looking forward to the next step.