Apple is doing a good job preventing others from tracing their users.

In iOS 14 there will also be a feature where, when you join different Wi-Fi networks (applies to new Wi-Fi networks that your device has never join before), your iOS device will generate a different private, randomized link layer address for each Wi-Fi network. Traditionally, operating system just uses the hardware's real link layer address, so as you move from one Wi-Fi network to another, those different networks can actually track you by correlating the link layer address they get from your device. Using different, randomized link layer address for different Wi-Fi networks takes away this tracking mechanism. (Apple reference.)