If i remember right when there was a 'scandal' last year - where journalist worked with transcribing voice data from google assistant recordings. They found out that it activated plenty of times without the key phrase(it is easy to see why it happens), and it did contain PII occasionally.

Probably by sheer 'coincidence', when google was being investigated - apple, samsung and few others shut down similar initiatives.

And with how hostile and profitable the advertising world is, I'll stay with 'guilty until proven innocent' mindset.