Why is the fact that there are no ads in Apple apps relevant to this post? None of this will stop you from using Apple apps.
Allowing people to use non-Apple apps won’t force people to not use Apple apps. People will only use non-Apple apps if they think it’s doing something better than Apple apps. If, as you say, Apple apps are the best, then people will use them even if Apple allows competitors into the iOS market. I do not see a single way this decision hurts any consumers.
Why is the fact that there are no ads in Apple apps relevant to this post? None of this will stop you from using Apple apps.
Allowing people to use non-Apple apps won’t force people to not use Apple apps. People will only use non-Apple apps if they think it’s doing something better than Apple apps. If, as you say, Apple apps are the best, then people will use them even if Apple allows competitors into the iOS market. I do not see a single way this decision hurts any consumers.