Always has been a prison. People who wanted to break free had to download dodgy software to "jailbreak" their iPhones and now it's so locked down that even that option is no longer possible.
The fact you nevertheless refer to this software as "dodgy" really shows how well Apple's messaging works to deter people from using it, even when their main argument against it is security (from what?).
Funny, considering that without Apple's draconian restrictions on user freedoms, IOS security is basically nonexistent even when compared to the low standard set by Android. It is true that the inside of Apple's jail feels safe, but in truth, there is much less keeping attackers out than users in.