I'm not sure if you'd call it a pivot, but Google Brain was initially an X project that was started well before the deep learning craze took off. They hired Geo

I'm not sure if you'd call it a pivot, but Google Brain was initially an X project that was started well before the deep learning craze took off. They hired Geoff Hinton in 2013. Investment in AI has been going on for a long time at Google, probably before Facebook/FAIR got seriously involved, but probably not Microsoft (MSR has been going for ~30 years and Chris Bishop started the Cambridge lab in '97 and they've long been known as a good ML group). It's not like Google wasn't using ML before that either. Search, recommender systems for ads, anti-spam, translate. Deep learning just turned out to be a lot better than the tools we used to use.