That’s a good observation, but Google really doesn’t control things the same way Apple does since they aren’t directly distributing Android for the most part. It would be hard to pull off that kind of synchronization with the handset ecosystem.
Google has very direct control over Google Play internal services which are effectively system-level services on android, and collects at least as much data on those users as Apple does on theirs.
The 1% of users running some custom Android build aren't really relevant here, Google scrapes up plenty.
> That is, almost two order of magnitude is uploaded by Android (3.6MB) than by iOS at startup, while Android downloads around a third (952MB) of the data of iOS (2.6GB).
The paper goes on into a lot more detail of tracking what identifiers are sent when and how often.
