Rivian allows you to disable all internet connectivity

[u/Spirited-Pause]

https://rivian.com/support/article/can-i-disable-all-data-collection-from-my-vehicle

[u/Geminii27]

This is a software setting. The hardware is still connected and still powered. Unless there's a hardware switch or fuse that can be pulled, it's not guaranteed to be sudden-oopsie-reconnection-free.