Funny thing is Apple's competitors don't make money. Apple has ~50% of all smartphone revenue and 87% of the world's total smartphone profit share - iPhone X alone was 35% of global profit share with, to your point, only 22% of the market. Less, even, my data shows 19% of shipments most recently. Samsung is next in line off the back of approximately equal shipment volumes. Everyone else effectively breaks even or loses money. [1]
I do get it, my argument was that money is the only thing that matters. Their goal isn't to secure everyone's communication, it's to maximize profits. They're doing that by saying if you both care about privacy, we have a one-stop-shop that'll get you taken care of, but it's gonna cost ya - and your friends. It creates an implicit pressure for others to get on the bandwagon driving up sales.