Just make enabling jailbroken mode require a factory reset of the device.

The biggest risk is not elderly people but rather the owner giving their passcode to someone else, e.g. a repair shop, who then enables jailbroken mode without the owner's knowledge and installs malware.

You can mitigate this problem, and the elderly person problem, by requiring the phone to be factory reset. That way any jailbreak would be extremely obvious.

Mostly agree with you, but:

> My own parents are still relatively young and my in-laws are sceptical enough of other people that it’s currently safe but it won’t be so forever.

It is always interesting to me how people equate getting old with becoming dumb. I know there is definitely some age related decline that's inevitable, but if a person has grown up with computers, and maybe more importantly, has had a hacker and curious mindset while younger, it is not likely that they will suddenly become so naive and vulnerable, even when like 80.

What usually happens is that people lose interest in learning new things and keeping up. My own mom (who passed at 73) could never be convinced to use Whatsapp messaging, thinking it is something complicated for the young ones, and yet I currently know people in their mid 70s and even much older who are still as sharp as anything and use all the cool apps.

>>I want a device I can give the elderly in my family that they cannot be easily induced into doing insecure things on.

Perfect, I knew this would come up. It always does. "I don't want someone to convince my elderly relative to hack their phone and do something bad". It's such an infuriating argument - no, YOU can't have freedom to do whatever you want with the device you own, because MY elderly relative might get scammed.

>>I would prefer to just give them a device that can’t do that.

There are a number of phones available that can just do calls and nothing else. If your elderly relative cannot follow the most basic advice of "don't listen to people calling you and telling you to do something on your phone" then that's all they should use.

Like, honestly - if you think your elderly relative will follow a 20 step process to go to a dodgy site, run a bunch of commands to jailbreak their phone, then download an alternative store to MAYBE download a dodgy bank app....what stops them from just following instructions from a scammer to send their money urgently to this account they named because the bank is doing maintenance on their servers and the money needs to be moved now or be lost? I love these "elderly relatives" who simultaniously don't have 2 brain cells and will follow jailbreaking instructions but who won't fall for any much easier scam involving direct transfers, gift cards or even good old fashioned cash in an envelope.