People, if you want to discuss your fetishes or crimes or whatever you want around a smart speaker, just unplug the damn thing. It's not that hard. I got them all over the house because I'm an automation geek but I'm well aware of what I say around them. With a Pihole on the network, I don't get targeted ads either.
Also, they don't send your audio to their servers 24/7. I've verified this myself with Wireshark. That would be a hell of a lot of server resources they would need, and they can get info easier just by profiling and fingerprinting you online.