Why can't they just put up a big, red warning: "Never enable software installation if someone asks you to (over the phone or via message). If you're unsure, check out this article on scams."?
> "Never enable software installation if someone asks you..."
Imagine a situation in which a frightened, stressed user sees such a message on their screen. Meanwhile, a very convincing fake police officer or bank representative is telling them over the phone that they must ignore this message due to specific dangerous emergency situation to save the money in their bank account. Would the user realize at that moment that the message is right and the person on the phone is a thief? I'm not so sure.
What if there is a 12-hour delay to unlock "power user mode", and during that entire 12-hour unlock period, the phone keeps displaying various scam education information to help even an unsophisticated user figure out what's going on? Surely Google can devote a few full-time employees to keeping such educational materials up to date, so they ideally contain detailed descriptions of the most common scams a user is going to be subject to at any given time.
This would help for sure. Ideally, the phone should stay in "expert mode" for a limited time only, like 1 hour.
However, there is still a danger that scammers will call after 12 hours, and they will be more convincing than educational material (or the user may not have read it).
> However, there is still a danger that scammers will call after 12 hours
It is unlikely it will work. Scammers are talking all the time and creating a sense of urgency, people have issues to think and listen at the same time, and they tend to drop thinking completely when in a haste. 12 hours of a break will give the victim time to think at least. Probably it will give time to talk about it with someone, or to google things.