What is a scenario where this actually happens, though?
Imagine two people live in the same residence. One is extremely privacy conscious, doesn’t even have a Google account, and the other doesn’t even run an ad blocker. Both have the same phones on the same OS version, and for sake of argument, both are on the same ipv4.
Does this mean that, if the privacy conscious person opens a private browsing session on their phone and visits some websites, they start getting ads their roommate should be getting? At what point would Google know “this is the same person, show their targeted ads”?