99% of people buy hardware unaware of the how the software locks them into a walled garden.
The vast majority of people aren't thinking "Wow, I love how Apple takes away my freedom and forces me to use apps even if I might want to use something else", they're buying an iPhone because it's shiny and is what they're familiar with.
Those people deserve to be afforded user freedom and to own the devices they purchased.
You're in the minority. A tiny minority at that. Of all the 'normal' people I know that own iPhones I can tell you now that not a single one of them thinks "gee if only I could <do thing you seem to imagine they cant do>".
The average user doesn't give a crap if you can sideload some random app that is only needing to be sideloaded because its likely dodgy as hell.
Also if someones using an iOS device and is skilled enough to need to sideload then they'll know full well they CAN sideload by deploying an app from xcode.
99% of people don’t care about what you call a “walled garden”. They have no more desire for that “freedom” than you yearn to install third-party firmware on your dishwasher.
Go up to a random stranger and ask how much it would be worth to them to be able to sideload apps or have a bash terminal on their iPhone. They wouldn’t even say “zero dollars”, they would just laugh.
I am a professional iOS developer and I also couldn’t possibly care less.
The vast majority of people aren't thinking "Wow, I love how Apple takes away my freedom and forces me to use apps even if I might want to use something else", they're buying an iPhone because it's shiny and is what they're familiar with.
Those people deserve to be afforded user freedom and to own the devices they purchased.