Roughly half of lower-income Americans don’t own a PC[1], and we have some of the highest market share in the world. I don’t have numbers handy outside the U.S. but again, 1 billion PCs doesn’t cover much of the population.
The trend has been obvious for years: more and more people do all of their computing on smartphones.
89% of US households have a laptop or desktop. That doesn't mean each family member has their own, whereas it's more likely to have each family member have their own phone, say on a family plan. But in terms of revenue generating opportunity, if someone cannot afford a laptop or a desktop, they will not own an iPhone either, which accounts for 2/3 of mobile revenue, and they are not going to be running your complex smartphone app on their discount android device, so you haven't responded to my argument at all; you keep fixating on counting the number of devices rather than looking at actual addressable markets and the best way to generate revenue from people who can afford to pay for your product or that advertisers will pay to market to.
Just to throw some numbers out there, as of 2018:
iOS revenue: 47 B. (global, all sources, software, ads, etc) [1]
Google play: 25 B (global, all sources, software, ads, etc) [1]
Global software revenue: ~450 B (global) [2]
Total software revenue (US only): ~260 B. [3]
You are right about the 90% and 10%, but it's not pointing in the direction you think. So you can keep counting devices with very different characteristics and insisting that one number is higher than the other, or you can start counting dollars.
The trend has been obvious for years: more and more people do all of their computing on smartphones.
[1] https://www.pewresearch.org/fact-tank/2019/05/07/digital-div...