Here's an alternative view...

The Tivo is today's equivalent of the mixed tape of a couple of decades ago. Let it go.

The idea of recording content that's blasting down a pipe at a time chosen by the source is so archaic, I can't believe Apple enthusiasts are actually in favour of such a distribution model.
I can appreciate your point of view. Again though, dismissing the DVR idea because it is old tech makes sense when old tech is actually on its way out. The fact is that we (almost) all still have television being pumped into our homes in one way or another (cable, satt, etc) and that is likely to continue for a long time. We already pay for that content and the law allows us to record that content for personal enjoyment at a later date.
I would much rather the distribution model be more along the lines of how you envision it. But it is not that way. And it probably won't be that way for a long time- if ever; there's simply too much money in it as is for the entities that largely control the pipes so one way or another- they will get theirs.
Give me on-demand, top-quality content at reasonable prices so I get exactly what I want, when I want it, where I want it, on the device I want to view it on, and that's the future. That's where Apple is right now with music and that's where I hope Apple is going with video next!
Again your vision is excellent. However, Apple is far from that vision right now. Because they lack a lot of content availability, the "on demand" piece fails unless a person is happy with the limited offerings that are available now.
Because Apple chooses to limit the quality of the content to handicapped 720p at best when there is an awful lot of the same content available at higher resolutions and higher bitrates, means we can't get "top quality" now from Apple's system. And if by "top quality" you mean quality of the programming (NOT quality of the audio/video), Apple fails there as well because a lot of highly-rated content is NOT available from iTunes.
Lastly, do you actually think Apple's pricing for programming via iTunes is "reasonable prices"? If so, you appear to be in a minority. In a good number of situations, it is cheaper to buy the same programming on DVD or BD than to buy the iTunes (more compressed) versions. And again, if a person doesn't mind the commercials, or doesn't mind editing the commercials out, a great deal of most popular network programming can be had for "free" via over the air- free being the most "reasonable price" of all. Options like netflix delivers a lot of catalog content for much less than renting or buying individual movies via iTunes. Etc.
Now, I'm a huge Apple fan and I own an

TV AND I completely appreciate your stated vision of how things could/should be. But I also argue that Apple is far from that vision now (and they are not alone), and it also seems unlikely that sticking to their guns as they continue to do with a tired hardware platform and a "buy it all from iTunes only" distribution concept will result in us ever getting to fully realize your stated vision.
The best shot at getting there would be to build a next-gen

TV with the features that BUYERS want to buy (whatever they are),
get an
TV in every home, then phase out the "archaic options" as those lose favor with the customer base over time. If

TV was in every home, content providers would want every bit of video ever created available in iTunes (that would cover everyones "on demand" needs), competition (and ROIs on such a massive amount of cheap distribution) would pressure content providers to compete on (lower) prices, and higher qualities (that would cover "reasonable prices" and "top quality").
There would still be issues to overcome. For example, those in control of the pipes that deliver such content- generally the cable & communications industry who compete with similar content- might simply raise prices of broadband delivery to make up for falling television subscription revenues. But nevertheless, only by getting massive adoption of a next-gen

TV does it seem favorable that the vision- as stated- could be realized (for everyone). In your case, that vision may be realized now with things as is, but there seems to be plenty of people commenting in this thread that are looking for more from Apple &

TV.
Give people what they want, and people will buy a lot of what you're selling. Give people what you want them to want, and people may buy a lot if you guessed their needs exactly right, but will probably buy less since you're not hitting their target. Guess wrong and wait for buyers to come around to the company way of thinking and you generally end up with very slow market penetration. Which of these seems the closest match to

TV "as is"?