Well the answer to that question has been answered. Google can prevent cross app tracking in Android. In a recent announcement they confirmed this and said they are actively working on their own version of this. As you might expect Google’s version is going to be very different than what Apple rolled out. Apple is requiring consent from the user for each app that wants to perform any cross-app tracking. This is in line with many privacy regulations outside of the US.
It seems that Google is going to tailor their feature with advertisers in mind. They are going to take feedback from advertising companies and integrate this into how they approach this issue (translation, they are not going to do a lot about it). Google also wants to allow advertisers a chance to prepare for and plan for changes to their ad systems to they can work inside the new system. Allegedly Google plans to continue to collect all app data on their phones and transmit “anonymized” information via API to advertisers.
This means that Google has access to all your data (if you are using Android) and can sell access to the API to other companies. This does not sound like a move to preserve privacy at all. It is a move to put Google in a position to make money off data that it will collect. They are also likely to continue to collect additional data about users of Android devices so that their services have an edge on the competition.
Google can put all the flowery words they want around this, but at the end of the day they are an advertising company. This means that they are not likely to cut off their own head when they can find a way to give themselves an edge and make money off their own “privacy” feature.