Semantics. Most electronics manufacturers outsource the actual fabrication, but that doesn't mean that Apple doesn't make their computers in every meaningful sense of the word.
Which you can only buy if you own a Mac. So the profit margin for a Mac covers future OS upgrades... break it down however, you like, but the combination of software and hardware certainly makes money. So they gave me 2 upgrades of OS X since I bought my Mini... Microsoft has also given me 2 upgrades to Windows since I installed Windows 8. Can you say Microsoft isn't making money on Windows?
No, they can't. When you consider all of the manufacturers, models, and types of hardware components out there, there are literally billions of combinations. How is one company going to test that?
Welcome the world of class drivers and of open source. Just because thousands of people collaborated to write the drivers that are included in the distribution doesn't mean there's no driver.
The Linux kernel was written from scratch, but the specifications and API's are based on Unix. It's more fair to say Linux is a Unix clone. "Ported" is the wrong word, but the intent of the statement is correct; Linus literally set out to write Unix on PC's. Since there was no free Unix on x86 at the time, his kernel was obviously written from scratch.
Also, it's worth noting that the tools that are part of a functioning Linux computer, the shells, the utilities, and the GUIs were written by other people and were originally pulled from Gnu Unix. In any meaningful sense, Linux is a Unix derivative, plain and simple.
Again, WTF? Apple's computers are built by Apple and its contractors from scratch. Do they manufacture the CPU's and chipsets? Not for their laptops and desktops, but they make the CPu for the iPhone and iPad. They fabricate the motherboards (of their own design), the cases, the software, the keyboards, the mice, the touch screens, the power supplies, the... well, need I go on? Are Dell and HP just "marketing and packaging" companies? How do you even define a hardware company if not by that measure?
The EXACT same hardware is inferior? What? In what world does that statement make sense? And no, you can't purchase an Apple motherboard from anyone but Apple. Hackintoshes work because hackers replace part of OS X's code with code that's been hacked to ignore the Trusted Platform Module (or however Apple uniquely identifies a legit Apple motherboard.)
Also, if you consider what you get on a vanilla Mac, you get a bunch of stuff that PC users have to pay for. Garage Band alone would cost around $100 on a PC. Then there's the office stuff that comes free (bought a copy of MS Office lately? Did you spend LESS than $300?)
IMO, the biggest reason Linux has lasted 15 years is because it's free. If desktop Linux cost money, it would have died right alongside another superior operating system, OS/2. Why is Linux in cable boxes, toasters, routers, microwave ovens, cell phones, cars, airplanes, the International Space Station, and even watches? Because money. It's cheaper to use a free operating system than to write one from scratch.