I think it’s more a sign of the times than Apple being Apple that they don’t tell you what hardware you buy when you buy one of their systems or how it is connected. Television manuals used to contain hardware schematics, car manuals used to be way more detailed, etc.
Apple also had detailed info on their hardware. The Apple II reference manual had schematics, mapped it to the PCB, described what each part did, described 6502 assembly and had an assembly listing of the monitor ROM. The only thing missing to build a copy, I think, was an assembly listing of the Basic interpreter.
The phone book edition of Inside Macintosh also had info on the hardware, but a lot less of it.
The keyword being had, but Apple has always been on the more closed side --- Inside Macintosh was far more pretty but overall less informative than the corresponding IBM PC Technical Reference books.
The Apple II was useless on arrival unless you could program it yourself. The iPhone is useful for 99% of customers while providing no on-device programming. Weird analogy.
Apple also had detailed info on their hardware. The Apple II reference manual had schematics, mapped it to the PCB, described what each part did, described 6502 assembly and had an assembly listing of the monitor ROM. The only thing missing to build a copy, I think, was an assembly listing of the Basic interpreter.
The phone book edition of Inside Macintosh also had info on the hardware, but a lot less of it.