This might be helpful: https://support.apple.com/en-us/HT211227

> To reduce this privacy risk, iOS 14, iPadOS 14, and watchOS 7 include a feature that periodically changes the MAC address your device uses with each Wi-Fi network. This randomized MAC address is your device's private Wi-Fi address for that network—until the next time it joins with a different address.

iOS 14 is in beta, but has been pretty solid for me. https://beta.apple.com/sp/betaprogram/

Since Android 9 there is an option to use randomized MACs for the actual connection (not just probing).

Realistically nothing, however if they're using a Stingray to target large swaths of people, you're more likely to avoid getting your phone pinged on WIFI. Not to mention going after specific MAC info from Xfinity takes a long time.