I feel like service revenue is going to be Apple's "oil curse". I get why they need it in the short to medium term, but in the long term it removes the fear of death that used to originate from having to release groundbreaking (and successful!) hardware products every few years. And as they grow the service revenue, the fear of death will wane even further.
Maybe non-terrible Siri needs to be a subscription service, instead of a phone-selling feature.