The concept is that you're carrying over the same general topology of the real data but in a way that is effectively non-sense. This allows you to build ML models that are representative of the parameters of the true data which you can then use for inference systems in production.

It's a technique we've used in the DoD a long time and it works ok when everything is perfect. There are a lot of boundary problems like being able to troubleshoot bad data if you are doing your initial analysis with the transformed data, having DS's actually grok the problem-set since it's abstracted etc...

Edit: It's worth noting that this is a technical solution to a policy/legal roadblock. As organizations mature into better data governance, they are pushing more fundamental changes to governance that gets at these problems where solutions like this will no longer be necessary. For example, hiring data scientists into the groups that have access to the raw data (in our case hiring data scientists and giving them security clearances).