The Portland system has a tap in system that charges you each time you tap the phone against an NFC reader. You are charged a flat fee. You tap your phone every time you board a train, trolly, bus etc. However once you have paid $5 ALL your charges are combined into a single all day $5 ticket. The caveat is you must use the same credit card for all the transactions. This tells me that Portland TriMET system does have at least some information about the people using the system.
I am pretty sure that is how it works in TFL except that the price is determined by the distance and zones travelled which is calculated by the entrance and exit gates, which both require a phone tap. I have the same debit card on both Apple Pay and Google Pay. I wonder whether I could use both in London without being charged for two Travelcards, i.e. is the tracking token linked to just the payment card or also the phone?