I agree mostly with you, especially that last line! I just think we disagree on how big that sliver is. I think it's at least 20-25% of the public that is very uncomfortable with the technology they use, and with the right social engineering, absolutely can be taught to do harmful things to themselves.

You (or another commenter) are right though that blocking sideloading eliminates but one avenue for this abuse, which at first makes us feel good that we then shouldn't have to give this freedom up! Now, the bad news is that from Big Tech's pov, the open Web is the next enemy in the crosshairs. The future "Sheep mode" may simply be App Store (only sanctioned scams, paying their 30% cut, are allowed there!) + a "Web Browser" without an address bar, which can open any of the "Thousands of Safe Sites" on the OS Vendor's allow-list. Getting on the list is of course "easy," and just requires a $999/year subscription, and proving SOC2, GDPR, and CCPA compliance.