For some reason Apple is extremely stringent with their Servers / Cloud Investment. They were late to building their DC, late to owning their CDN ( despite being huge in volume ) Basically Tim Cook has a model that they should not own any "asset". the Asset Light Strategy. Compared to Google which is beating any AI , Deep Learning problems with brute force, and optimise later.

Even their Maps are late, 7 years later since the first apology of Apple Maps they still aren't anywhere close to Google Map.