Unfortunately, that applies to way more than just Apple products. You can't unlock the bootloader on many modern Android phones sold in the US, and you can't replace the primary bootloader on any phone (with very few exceptions), anywhere, due to the hardware implementation of secure boot, which requires the bootloader to be cryptographically signed by the owner of the keys (the vendor).

There is no option to replace the keys with your own in the device that you purchased and "own".

Don't even get me started on Smart TVs and other IoT devices. All of a sudden, people don't care about computer freedom as much if you just stop calling it a computer.