Apple accounts for almost all of the remainder. You think Windows Phone and Blackberry are anything more than a rounding error at this point?
Those Android stats are worldwide, in wealthier countries Apple has a much higher share - nearly half in the US, for instance. They also get features on every phone they sell, whereas Google won't get their assistant on the large majority of the Chinese models, that have googley bits stripped out. If Google's assistant ships on the S8 I'm sure Samsung will do their best to hide it and give Bixby top billing, which would further hurt its share. Android may have 80%+ of share of the market, but Google's assistant will never sniff anywhere close to 50%.