Yeah it is because the CPU and GPU are customized for Apple. You'd have to recreate them (which probably would require a F500 company like Amazon or Google) or write a translation layer similar to WINE (which would need a couple dozen expert coders). Not worth the effort for knockoff phones.

Knockoff iPhones would sell like hot bread.

You can buy them at "the market" in Shenzen. You can even put in original Apple logic board and run iOS - and have crazy things like double storage, memory cards, 3.5mm output, etc. You have to build it from parts though, no one is selling a complete product AFAIK.

I would be fiercely interested in any more details around this. I'm sure many of us have seen Scotty from Strange Parts doing his headphone socket project, and the franken-phone built from spare parts, but it sounds like you're suggesting something even more than that.

Citations, please!

Sorry, that's personal anecdote, not something I got from youtube or articles that could be cited. See my other reply: I'm not really suggesting anything more than what you can see on Youtube, just that knock-off iPhone parts that are easy to manufacture (body, battery electronics etc) exist - not the logic board though.

Afaik, those are not really knockoff as in a Gameboy replica. They're still using the proprietary Apple mainboard and all for the most part. What they did to double the storage was to desolder and solder back in a different storage with different capacity with the image from the original storage cloned onto, a process which kinda costly amd very risky as the components aren't designed to be plug and play like desktop components

Ref: Youtube channel "Strange Parts"

There are stores selling knock-off easy to manufacture parts like body, some basic electronic components etc, and yes, as I said, the logic board itself needs to be original.

They still can't run iOS apps from the App Store. They are encrypted when downloaded and only decrypted at runtime. Decrypted apps can be offloaded from a jailbroken phone and then re-uploaded to a pirate store though.

Same like Hackintoshes, right?

You would probably need to hack the OS to disable updates etc to prevent Apple from remotely bricking your device.

Wrapping it with a firewall would be the easy part.

That's be the easiest part. You can just grep the binary for apple domains and replace them with your own.