Sorry for assuming you'd be able to extrapolate from one example. It could be at any level of the funnel from your local machine to the wider Internet. Closer to home: this sort of fingerprinting could defeat things like MAC randomization in a PSK-authed business/university setting if those IT departments had some reason to want to track you.
I once worked at a company where the Security team were very proud of this and all the other tricks they used to catch leakers by figuring out who was on campus, where, at what time, usually via fingerprinting personal devices carried alongside corporate devices.