I think it’s a little more subtle: the ad focus means they’re unwilling to consider other revenue models or deeply appreciate how customers are different than high volume ad impressions.

The Google+ and messaging debacles are obvious examples but I think GCP and G-Suite were also seriously held back in a way which an independent subsidiary which had to make a profit on its own would not have been. Their executives just weren’t sweating the way they would have if they knew their shares would go down when they didn’t execute well. Contrast with AWS, whose leadership are running the service in a way which makes it clear they have no plan B involving ongoing subsidies from the parent company and thus aren’t blowing off customer support, features, security, etc.