MKBHD (one of my favorite "Youtubers") just posted a video actually comparing Siri to Google Assistant. It almost seems like a bit of a myth buster since there weren't huge differences in the two services. In fact, Apple often shows more complete information and shows it faster. For example, it could give a current pre-season NBA score, where Google showed a regular season score from last year. Google was better at saying exactly who the POTUS was, but couldn't pull up pics of "German Shepherds," while Siri could.
Also, he asks to see pictures of cats. Apple went to the web to get pictures, while Google pulled up a couple cat pics in his Google Photos library. If he had cat photos in the iOS Photo app, it would have launched his cat pictures rather than photos from the web. I tried this with my iPhone and it showed every cat pic in my library rather than the two pictures that Google Assistant pulled up in his demonstration (although, he may only have two pictures). If you want to see web pics, in my use, I found that saying "show pics of cats off the internet" is what works. This brings up the fact that you have to be specific about what you want or these assistants will make the choice for you.
In other words, some of the differences, that he used in making his final decision about which service was better, were related to how he was using the device. What I found interesting is that Siri often gave a better, more complete response and it typically looked better on the screen. It was also faster at gathering the response most of the time. Here is the video link, so you can see for yourself.
The Wrap Up
* In the case of Mossberg, I believe his agenda is to put pressure on Apple to make Siri better. So I can't really complain. However, they are constantly making changes, so I am not sure that his pressure will really make much difference in the overall Siri service. It already works pretty well, but it could be better with understanding less specific language. Though, all of the services are at the point where you have to be specific, so it is par for the course.
Finally, and this is the point of all my Siri specific articles, I can't think of anyone I know that would switch from iOS to Android or from Android to iOS based solely on how these two services compare. Well, I could see someone moving to iOS because this shows that the services are very similar, but Siri does it without invading your privacy. Right now, Google Assistant isn't so good that it makes the sacrifice worthwhile....well, unless you are the kind of person that takes pleasure in clicking on spam emails and typing in your credit card number or social security number.