I think you misunderstand me, so I'll try to clarify.
I'm not saying that ordering a third-party drive from Amazon is some insurmountable obstacle, I'm saying it is a small inconvenience that will result in a measurable difference in behavior because defaults matter (often much more than we think - see the studies on opt-in vs opt-out 401(k) enrollment).
I'm also not arguing that there will be a smaller selection of ripped movies on bittorrent or whatever. I'm arguing people will use ripped movies less and, in particular, will use rips of their own collections less (and even watch their own collections less on their computer, but I think that effect is less interesting) because the optical drive is less convenient:
- they're less likely to have it at all (as argued above)
- it might not be at hand when you want to use it (particularly if you're not at home)
- using an external drive is flat-out physically less convenient than an internal one (particularly if you need to keep your drive and computer plugged in and/or have other peripherals in the mix...)
Why would it matter that people are ripping their own collections less? Because the norms around ripping your own collection come from CD ripping and the norms around downloading movies from bittorrent come from piracy. Many more people are willing to do the former than the latter. In other words, ripping your own collection is very useful and is fundamentally different from pirating. The convenience of ripping DVDs you own is an important factor that will affect people's video consumption and I think that effect is growing with time.
I'm also not claiming that there is a complex conspiracy going on. I'm saying that, from a consumer's perspective, Apple's judgment about whether or not "the optical drive is done" is compromised. For that matter, this compromised judgment may manifest itself consciously or unconsciously.
Apple decision-makers might unconsciously make any or all of the following mistakes (as well as others):
- underestimating the usability of DVD rips
- overestimating the usability of iTunes video by not considering niche drawbacks (e.g. subtitle issues)
- underestimating the desire of people to have video on non-Apple devices (e.g. Android phones or tablets)
To put it another way: Even though Apple has better technical judgment overall, I'm more willing to trust Lenovo or Dell's judgment about whether or not "the optical drive is done" because they don't face the same conflicts of interest that Apple does.