Are you implying there's a big percentage of people getting their money stolen because they rooted their phones? I'd like to see some data on that if so.

I don't know the reality, but my guess would be that it's the inverse of what you proposed; a significant portion of fraud cases identified by banks involved a rooted phone. From the defender's perspective, this could be a problem they run into over and over again, and take an outside place in their eyes.

I think the point is that phone apps are more secure than, for example, web apps.

Users that try to use mobile apps as if they were web apps, disabling location, and security features are just flagged by numerous security mechanisms.

Probably. I know a guy who roots phones for older people or friends parents, installs pirated games and such for them and making sure it is locked down in certain ways for the older generation.

In other words, the correlation is that older people are more likely to have a rooted phone and are more susceptible to fraud.

Dunno how widespread this is, just something to keep in mind.

Perhaps people who unknowingly bought a rooted phone. I don't know how frequent this is, but it would be the only case it would matter.

At the cost of making society even more dependent on Google and Apple.

“Every high civilization decays by forgetting obvious things.”

Quite a contrast from the quote about civilization advancing in proportion to the size and scope of things it can achieve automatically.

Dug it up. Alfred Whitehead:

It is a profoundly erroneous truism, repeated by all copy books and by eminent people when they are making speeches, that we should cultivate the habit of thinking of what we are doing. The precise opposite is the case. Civilization advances by extending the number of important operations which we can perform without thinking about them.