>they could convince non-technical users to switch to an unofficial app-store
They could, but they're absolutely not going to. Every barrier you put between and user and installing your app is a percentage of those installs that you're losing. Doubly so for "non technical" users, who can barely work the app store in the first place. No company of that size is going to lose that many downloads just to steal a few more downloads.
>then I realised that probably most Android users have those horrible carrier and OEM locked-down devices that make it harder (if not impossible) to change system settings or add other app-stores.
Stock android makes you jump through hoops to install third party apps, and for good reason. No, it's not because "OEM locked-down devices", the reason you don't see it on android is because it doesn't make business sense.
This has been my feeling for years, and why I think it'd probably be in Apple's interest to let people sideload apps. They could still require them to be signed, but otherwise be hands-off. The vast majority of users wouldn't go through whatever hoops were necessary to set that up -- even if it's just the single hoop of flipping an "allow non-App Store apps" switch in Settings -- but making it possible to do that gets them out of a lot of the regulatory imbroglio they've been heading toward. (I also can't help but feel it's necessary in the long run if they're serious about the iPad in particular being a general purpose computing device rather than an application console.)
When it comes to a mainstream app like Facebook or TikTok that already has network effects and a critical mass of users, people will put up with significant efforts to alleviate their fear of missing out, including sideloading the app.
They could, but they're absolutely not going to. Every barrier you put between and user and installing your app is a percentage of those installs that you're losing. Doubly so for "non technical" users, who can barely work the app store in the first place. No company of that size is going to lose that many downloads just to steal a few more downloads.
>then I realised that probably most Android users have those horrible carrier and OEM locked-down devices that make it harder (if not impossible) to change system settings or add other app-stores.
Stock android makes you jump through hoops to install third party apps, and for good reason. No, it's not because "OEM locked-down devices", the reason you don't see it on android is because it doesn't make business sense.