Android is not a choice for iOS users, it's not a seamless switch. The solution as I see it is that apple could still very well protect users from "trojans" but have an opt-in for 3p app installation. A button that says "I want to install apps from anywhere, I know the risks".
If I pay for the hardware, as a customer, I should be able to do whatever I want with it. With the iPhone, it feels like I'm renting rather than owning. I worry that's the direction apple is taking Macs in with the M1.