If you had good backups, you didn't had to pay until now.
But to make the data public, they have to download all the data first. This might be detected.
I know from several companys who did set up the complete network again.
The most prominent company I know at moment is Pilz (pilz.com). There website was almost down for a month. Now after 2 months it possible to download datasheets and manuals again.