100%. I tested mine with calls and making sure the wifi and Bluetooth didn’t go through.

You can also buy faraday bags, if you want a phone available but not online. But it’s still there physically so burner would still be a good choice.

Basically means that the core OS files and systems can’t be changed. Everything else is stacked on top, and usually it means that you can rollback to a previous OS version if an update breaks something, without relying on any other image backup software.

Usually results a more stable reliable system, or at least one that’s easy to revert to working.

The downside being a reduction in flexibility and customizable options, and most programs need to be “containerized.”