> you leave the device at home while you go out on your dissidence business

This is not so simple at all. Mobile phones are required everywhere now, from reading a menu in a cafe to entering a building with QR-codes (against corona, of course). I am not even speaking about importance of communication with other people.

Also, no government turns into a tyranny overnight. It happens slowly and most people will not be aware of it until late, including dissidents.