I have two Amazon Echos that I never use, but they apparently burn GBs a day 11 months ago
I had a similar issue 2 years ago[0], tracked it down to a device metrics hostname and then blacklisted the DNS for it. That stopped the huge data use and seemed to have zero affect on the device functioning. It's still working just fine today with that host blocked.
[0] https://www.marcroberts.info/2023/echo-show-uploading-data-c...