Because it's the benchmark that other photo app alternatives strive to be. It's a nightmare privacy wise, but Google built the best solution and a lot of iPhone users just assume Apple was the leader without trying anything else.
Thankfully there is immich which is working hard to duplicate the feature set without the privacy invasion.
It’s dreadful in the UK. The face matching is on device and just doesn’t work. I can’t search by detected objects. It doesn’t integrate with iMessage for sending large batches of photos via iCloud.
Thankfully there is immich which is working hard to duplicate the feature set without the privacy invasion.