Unity aren't exactly in the DRM business, and there is really no chance they're going to do something silly like licensing Denuvo for every single one of their clients just to obfuscate a piece of analytics code designed to make them money; stuff's far more expensive than what they'd earn from it. They're not going to build something remotely Denuvo-like, the best you can hope for is obfuscation that only has to be cracked once that gets cracked in days.

My guess is they're not even going to bother doing HWID-ish nonsense and will just hope that identifiers from the previous install hang around, which will often be the case on Windows PC anyhow (a little more complicated on other OSes). Hitting the uninstall and reinstall buttons in Steam doesn't do much other than deleting the game's files and re-running redistributable installers the first time you play the game.

But on Android/iOS where this is really targeted at, that approach simply doesn't work. The only stable thing apps can get across a reinstall is the AAID/IDFA advertising identifiers and that can be turned off or changed at will. Either Unity has found a novel solution (which is a one way trip to Apple's shitlist) or they're just bullshitting this change to appease the population while not actually changing anything. Since they did their prep work so badly that they couldn't even answer whether app updates would count, my money's on the latter.