Well nowadays you individually track by using mac addresses and other network information from the devices within range. Cisco has some creepy real time maps of your location with each person walking around and all their previous visits etc

Modern phones connect with a randomized MAC address. So yes, you can track a person around, but you will need another system (like the WiFi login page) to match MAC to identity.

Really? I thought it was only I phones that did that though?

Android has been doing this for a while, too

windows 11 also has it.