Apple probably uses a logic to generate the random mac address depending on time of day, etc. Unfortunately, while advertisers may not be able to track the owner of the phone that easy anymore, I'm sure the law enforcement has a copy of the logic to reverse engineer to find the owner of the phone. Having said that though, I'm sure the law enforcement has other tools at their disposal to track one down.
I think the better solution is to use TASKER to disable automatically when leaving the home/workplace and re-enable it when entering home/workplace. It works surprisingly well. Ya, I'm aware that tasker does not run on IOS. The choice is still yours though -- android or not android.