When Apple first started using it, they were responsible for 25% of all WA traffic. With Alexa, I assume that the majority of WA's queries are coming from smart assistants at this point. (https://9to5mac.com/2012/02/07/four-months-in-siri-represent..., https://www.theverge.com/2018/12/20/18150654/alexa-wolfram-a...)
When Apple first started using it, they were responsible for 25% of all WA traffic. With Alexa, I assume that the majority of WA's queries are coming from smart assistants at this point. (https://9to5mac.com/2012/02/07/four-months-in-siri-represent..., https://www.theverge.com/2018/12/20/18150654/alexa-wolfram-a...)