Hmmm, I don't have a solution but if it was common for elderly people to have no passcode then they'd be a huge target for stealing them and emptying their bank accounts.
That's why I get that the default should be a passcode. Same reason Windows Update probably should automatically update. We live in a problematic world and these options are the least bad.
My Grandma's solution to this problem is to not bring her phone with her when going to public places, and that's probably the right call if you can swing it.
It's one thing to be a default. It's another thing entirely to employ dark patterns and annoyances to coerce/trick the user into doing something they don't want to. The user should ultimately be in charge, and the machine should get out of the user's way.
Which bank allows you to empty someone's bank account if you find yourself with an unlocked device in your hand?? If was a criminal I'd be waiting outside their branch and snatching people's phones out of their hands right there, so I'm pretty confident that's not a real scenario.
While Apple tries their best to avoid it, once you remove the passcode you can just open the Passwords app and see all the passwords. I wish they let me keep the passcode on device but don't require it after only 4 hours of idle.