iPhone alone is ~50% of US market share: https://www.statista.com/topics/2711/us-smartphone-market/
Android splits the rest.
Presumably people are buying the best phone for their budget and needs. Per OP, "They don't own a PC, this is the only way to safely conduct e-commerce." How many people with an iPhone do you want to bet have a PC, versus how many people with a "junky low-end android"? I'll bet you vastly more iPhone owners have another computer.
Like it or not, HN is an English-language forum, run by a company based out of SF, and a lot of commentators presume that context. I try not to, just as I strive to use clear English for the benefit of ESL speakers. But it is the default.
iPad is the device to follow the stream of the school lesson.
iPad is what the manager got for his Zoom meetings.
A necessity, not a luxury. Best security, best long term support, best re-sale value. If you're poor, an iPhone is the smartest choice. You need to AFFORD an Android device.