Pretty much all modern phones randomize the MAC address everytime they connect to a network unless the user explicitly says not to do that.
When there’s a Captive Portal like the screenshot, many devices use a random but persistent mac for that network avoid reauthorization after any network drop. This will make your access to the specific network trackable.
chuckles in GrapheneOS
(per-connection random MAC, for all networks, by default)
This is actually just part of stock Android. My Pixel 5 has MAC randomization on by default for new Wi-Fi networks.
randomize the MAC address everytime they connect to a network
+1, had issues using Android devices for presence detection because of this very useful privacy feature. Even on your home network, the MAC address and device hostname get randomized, unless disabled in the settings
Edit: typo
