I think it throws an internal error if you pull the fuse or cut power to it? I’m not entirely sure. I did it so I could disable it and if I needed to re enable it for any reason it would be really easy.

Here’s the Guide I used! I had to wing a little bit for my vehicle but it was still really easy https://quigs.blog/how-to-disable-onstar-on-the-chevy-bolt-to-protect-your-privacy/

I recently bought a 2021 vehicle that has OnStar. I knew this would be a concern, but luckily there was a guide online to replace the antenna with a dummy antenna that isn’t ever able to connect to the network to send data.

So that might be an option! It’s still collecting but it’s not sending anything back.