I've tried all the assistants, Google, Siri, Alexa. While I haven't tried a HomePod, I have used Siri from the phone, iPad, or even sometimes the Mac. When I first got into looking for a smart assistant in a Speaker, I started with Alexa, because of having Amazon Prime, and wanting to consolidate all my services into one provider as much as possible. I really like prime, and everything it has to offer. I tried the Google Home, mainly to compare the ecosystem. In the end I settled on Alexa s my main assistant, mainly because of amazon's flexibility and compatibility with third party services, and devices (smart home). I have been able to use my Apple Music trial with Alexa without any problems, but because of Amazon's recent lossless audio streaming within the last year or so, and since I have an Echo Studio, I think that may still be my primary music service, even though Apple Music also has good quality music as well.
As far as the texting feature mentioned in this article, haven't tried it yet. Usually I hear about such new features through the smart home channels I follow on YouTube. This time, I just happened to get notified through MacRumors about the feature. I may give it a try, just for the learning experience. However, I really don't see a real need for it right now. Typically I either speak to Alexa, or, I use routines that are automated to run on their own at certain times such as lighting, and turning the pedestal fan on and off and the lava lamps in the living room via smart plugs, and then the majority of my lights have smart bulbs.