I have the opposite experience on the HomePod mini, it's actually one of the thing that they are better at. My google home device is entirely useless to try to talk to if something is already playing on it. Compared to Siri that will understand me.
The issue is more with Siri itself being dumb and not that great.
Me: Alexa, Badezimmer 10%
Alexa: Ich kann nicht Prozent auf Spotify finden
*Five attempts later, it actually works*
(It was even less reliable in English)
Siri mostly hears the right words when I ask questions, and the voice keyboard (is that the same speech-to-text engine?) is correct somewhat more often than the swipe keyboard (although that doesn’t say very much as the latter seems to have become very confused as a result of me learning German).
For fun, I set Siri to English for a day and I was blown away at how much better it is. Both in recognizing requests, despite my accent, and in the quality of the voice synthesizer. Song requests became trivial and everything felt much more fluent. English Siri is even able to express emotions (happiness), which is something I’ve never heard in the German version.
“Not you, I want the Siri on my phone” or “switch to my phone/iPad”
“Skip the song on my iphone”.
Much worse is the responsiveness.
“I don’t understand”
“Still working on it”
“I can’t seem to be able to connect to the internet at the moment”
“I’m sorry. Can you please repeat?”
With all the on-device ML stuff I assumed they’ll get Siri to operate without the internet for basic recognition and switch to network mode for more complex use cases.
I always speak in a normal (or slightly quieter) volume and never have an issue with Siri activating.
My biggest issue is that my HomePods need to get restarted or power cycled periodically (e.g. after a power outage or network update). I wish they were a little faster and had better self-healing but generally work pretty well as room speakers which is primarily what I got them for.
Siri on HomePods are a disaster. You have to shout at it even for it to pickup what you are saying. Mostly when the volume is a little high.
I haven't tried Alexa and Google Assistant but from what I saw other friends operating it seems more of a smooth experience but I could be wrong.