But why Mac OS still allows competent users to buypass the security restrictions? Is it because they can't screw over MacOS users ? Or for some reasons the people that use Mac OS can be trusted but when you give the same user an iPhone his IQ drops and we can't trust him.

Come on, let's be honest this is in the first place in Apple interest, if Apple needs to sell in China then they made sure they handed over Chinese users data to the government, now if they want to sell in EU they would need to also put a bit of effort into it(I have no idea if EU market is smaller but money is money)