Why are you allowed to install things on your mac from non-apple sources if this is the case? I didn't have to go to an Apple Mac App store to download VSC from MS. I did have to click a prompt informing me that this program was downloaded from the internet and could potentially be harmful to your device type message, do you really want to install it, though. Has the mac landscape gone to hell with worse experiences, more malware or "software that makes them unhappy" because people can and do install software from non official Apple sources? It's literally the same company. Why does one being a "phone" or "mobile device" change things?
For starters: because the majority of humans on earth do not own or understand a PC or Mac or security in general and are only using a mobile phone. They just click on 'agree' and get on with their lives not understanding they just permitted a rogue app to plunder their savings account.
Social engineering will always be a concern. This was as much of a problem as it was 40 years ago, and Apple adding dialogues in the way of it doesn't stop anything, it just changes the path attackers take to reach ultimately the same goal.
If you don't want to understand security, fine: just don't be surprised when your personal information ends up in the hands of the wrong people. Everyone has a duty to understand their own threat model, and any reasonably comprehensive model would include Apple as an ultimately untrusted party. It's a zero-sum game, so they may as well just make it easier for me to use their devices when I'm forced to.
