If you haven't heard of Browser Fingerprinting you might want to give this article on Pixel Privacy a read.
This doesn't need cookies it's entirely based on the browser being used and the identification of the hardware it runs on. This means that incognito and cookie blocking is irrelevant as this technique doesn't require cookies and your machine is the same on incognito.
In the past days, we had this article posted
regarding using the GPU on a machine to further allow high precision identification of machines.