Brazilian here, used to people being robbed all the time:

Almost 100% of the time, robbers just want quick cash, ant they will either 1: steal the phone and try to sell it (most robberies simply fall into this first category) or 2: point you a gun and force you to unlock the phone in order to 2a: force you to transfer money from all your banking apps or 2b: take it unlocked in order to send messages to your contacts asking for money.

Most robbers don't have enough tech skills to even understand what a bootloader is. We live in techy social circles and we tend to think everyone has similar skills, while in reality, most people can barely use their devices. Just to illustrate how low are most people skills, if you format a drive with something like ext4, most of the population will be unable to access it.

The kind of situations where criminals will have high skills tend to be when they target specific people or companies, usually paid by crime lords or rivals. Such scenario is very unlikely to happen to the average joe.

Don't get me wrong here, I'm not saying that security measures are unnecessary. I'm just telling how most criminals operate around here, and highlighting how we tend to overestimate people's tech skills.