Re: Nothing new...
"Denial" goes both ways you know..
With the device being present in user homes it can be checked and they will get caught. This has not happened - over 4 years. They are not ambiguous that this is not done, the trigger must be detected and they light up when uploading.
People will understand "eavesdropping" and react far more strongly than facebook selling their "data" and "privacy". It is the reason for the allure of voice interaction - it is the predominant interface humans use.
When people write their diaries on facebook, they will care about privacy a lot more.
There are valid concerns with voice assistants, but "constantly uploading conversations" is not one with the current set of echo/home/siri devices & firmware. There isn't a shred of evidence other than paranoia and cynicism.
Bugs likely in third party implementations causing false detects would be a valid concern.