HomePod mini works with your iPhone for requests like hearing your messages or notes, so they are completed on device without revealing that information to Apple. This is the big differentiating feature, along with the seamless integration within the rest of Apple's product line. EDIT: HomePod does this too but it was not at a price point nor size that competed with other assistants.
Yeah, that'll be a differentiator for me. We have a few Echo Dots, which are pretty neat devices, but I'm not a huge fan of providing audio to Amazon and Google. Also, my neighbor was getting swatted and narrowed it down to his Echo Dots.
For someone who isn't a fan of providing audio, you seem to have willfully done so.
I am genuinely confused.