Also im pretty sure that majority of TV viewers do not watch TV on their PC or Mac monitors.
Actually, that's where much American TV watching is taking place--on web sites like Hulu.com, and many other sites run by networks...NBC's Saturday Night Live even featured a joke about it on the season-ending monologue opening by Alec Baldwin, when he joked that most viewers would actually be watching,as he put it, "...or more realistically, Monday morning at work on your computer." I actually watch most of my TV programming on the web, on Hulu.com...I can watch what I want to watch, when I want to watch. See--NBC's Saturday Night Live is the only remaining live broadcast TV show on American network TV, now just having finished its 35th year of live broadcasts--but now it's easy to watch TV on the web, on demand.
A 20-30 minute shot limitation is plenty; TV and video production scenes are not "that long". Look at videos today--scenes are often under 10 seconds.
Regarding higher-than current standard video resolution; higher resolution is considered a good thing by many people, and there are other vehicles besides standard cinema and TV display for delivery. Film and video directors can always shoot big, and reduce image size, plus there are also some very high-resolution cinema projection systems where d-slr video might cut into the OmniMax type of productions like the amazing skiing videos Warren Miller has been shooting. D-SLR video captures of amazing skiing tricks and rugged mountain-top vistas would be pretty easily shot with a 4-pound Nikon camera instead of a 25 pound cinema video or film rig that weighs even more and is dependent upon huge spools of film.
Who knows if this is a genuine camera; but proclaiming that there's no need for higher and higher resolution images has *never* stopped the camera companies from pushing the boundaries. Ever heard of the megapixel race? Is it necessary that moms shooting snapshots of their kids are shooting with 18 megapixel Digital Rebels and 15 megapixel Point & Shoots? There's a huge segment of shooters who will always buy the highest-spec'd product, for either reasonable reasons, or just for conversational name-dropping value. What's interesting though, is how absolutely pumped Hollywood insiders are about d-slr video; it is far, far better than 35mm film is for low-light shooting, and the capabilities of 24x36 sensors at capturing video images exceeds that of dedicated video cameras costing tens of thousands of dollars, or more, so the arguments that favor dedicated video cameras as the vehicle for advancements really are out of date, and don't square with realities. The point you seem to be missing is that the "video camera" manufacturers have totally,totally MISSED the market that Canon has tapped into...Canon has created a new paradigm, that of workable d-slr video, in the format of a camera (a Canon d-slr) that can use Canon EF, Zeiss ZF, and Nikon F-mount lenses, and is very,very low-priced yet has a huge sensor with amazing low-light capabilities. The video camera makers have been left flat-footed, doing what they "have been doing"---and that's the key you seem to be missing, by thinking in the past, and allowing your ideas of what is needed or what is possible to be based upon old-school ways of thinking.
A new paradigm rolled into town...maybe you missed its arrival...