I'll have to break it to you then: it's exceedingly easy to get the same use of data without an ID. The lack of national ID does not protect your privacy.
The feeling of protection hinges on how easy it is. A bit over ten years ago I was working in database "cleaning": merging databases from different organizations[1] into one coherent dataset. The data volumes were large, but other than that it is a simple task with low error rates and one which absolutely does not need global unique IDs.
This was ten years ago. The task only got easier since then.
On the flip side, the lack of national ID has inconveniences. How do you authenticate yourself when selling your house?
[1] Ethical work. These were needed either after mergers or because of the MS Access syndrome, where every department designed their own customer database.
There's a difference between possible and building a system specifically to help it happen.