I must be getting old.
To watch any video on a POS like a tablet gadget should be a pain, literally in the temples. You indicate an alternative laptop but I fail to find any evidence of its use anywhere in this article. It seems dishonest to mention it as an alternative but then never show any of its actual use. This article needs to be fully rewritten to correct this omission.
On point with what was published, an 8" screen to watch 9+ hours of video seems to be an exercise in pain inducement. The slightest flicker would drive me over the edge after a marathon like that. 9 hours of video playback on this device would be a difficult experience for an older person. The small screen, the awkward viewing angles due to constant shifting, the irritation in the ears from either audio phones or intently trying to hear any sounds through the small speaker(no stereo for you!) this thing has starts the list of annoyances in my estimation. Watching video on a larger display is simply not possible with this gadget as there is no connector.
Maybe you are getting old.
These tablets have a fairly large viewing angle, above most consumer TV products.
You can watch them on a larger screen, this tablet and most Windows 8.1 tablets inherently support both DLNA and Miracast even if they don't have an HDMI port.
They also have a USB port, and with USB to HDMI/etc connectors are fast enough to content directly to a larger display.
Some of the 8" tablets do have HDMI out and do have Stereo speakers, even if this unit does not.
As for sound, have you consider Stereo Bluetooth or even a wired headset? This is what 'young' people use when they are privately watching a video.
You can also just hook up the Stereo out to a Hi-Fi system, or use Bluetooth to an external set of speakers or Bluetooth input for your 1970s Hi-Fi system.
You seem to forget there are a lot of environments where people would WANT a smaller 8" display, like on an Airplane or in a Car, etc.
(I'm partially kidding you, because I'm probably older than you. You have outrage over things that are not only inaccurate, but you should understand may be important to others, even if they aren't to you.)