Google and its ad tech frenemies
The Cat & Mouse game with cookies is rather pointless these days.
Now that web browsers are so bloated they are like another OS they can be easily fingerprinted by sites pushing different fonts, blank .pdf's, webgl etc.
I've been looking at a script used by an advertiser that uses these techniques to fingerprint the exact make and model of the user's Android device to push fake virus warnings to trick users into installing questionable apps from Google's Play store, "free" iPhone scams and surveys.
The advertiser even boasts that they can bypass ad blockers but from my own testing uBlock Origin seems to be able to block the script as most of the infected CloudFront servers are blocked by the community supported Easy List.