The simple fix is a physical lock and a physical key - like the keys and locks first used on the Buick Model 10 and Cadillac Model 30 starting in 1908.
Even the most expensive mansions have doors with a lock with a key. (and they don’t have electric windows either)
The idea that a car needs an electric door handles is a stupidity that follows from a management that needs to keep “updating” the model, but can’t think of any genuine improvements.
My Volvo also doesn’t have physical locks except for one emergency keyhole under the drivers door handle behind a hidden plastic plate there are no other keyhole on the car. The key for it is this.tiny sliver of a key jammed into the fob you need a small screwdriver to get out or strong finger nails. The car also won’t pushbutton start if the keyfob battery is dead there is no mechanical start turn key it’s only push button start. People who know this carry extra 2032 cells in the glove box or back pack else you have to get an uber to a store for a lithium cell. Conversely if you leave your fob at home or inside a Tesla your phone app will open the doors and start the Tesla as your app is also a digital key. This happens to one of my lawyer’s who is also a good friend he managed to lock his key fob and cell phone inside his Model S and was about to break the glass I got a good laugh then handed him my phone and said login to your Tesla account with my app and open your doors homie. So modern tech has its advantages too. Has he locked his keys and phone in a older car he would have to call a locksmith or break the glass. I never carry my fob when I use the Model 3 I have two phones and one will always have charge in it enough to open the door and set it on the wireless charging station which is also the keyless read point.