A move that isn't entirely surprising due to how limited it was, Valve is moving back to focus on gaming more than anything else with non-gaming videos being retired.
From the news post:
For the past few years, we have worked on expanding Steam beyond games and software by building a video platform that supports paid and free video content. In reviewing what Steam users actually watch, it became clear we should focus our effort on offering content that is either directly related to gaming or, is accessory content for games or software sold on Steam.
As part of this refocus, we have retired the Video section of the Steam Store menu with an expectation that video content is discovered via the associated game or software store page, or through search, user tags, recommendations, etc.
Over the coming weeks a number of non-gaming videos will be retired and will no longer be available for purchase. Previously purchased content will remain available to owners.
Why is it not surprising? Well, it makes sense for multiple reasons. Did you ever buy and watch any movies (or other non-gaming videos) on Steam? I didn't, it's far easier to use a different service like Netflix, Google Play or practically any other where you could watch your content across pretty much any device and browser.
On top of that, Valve's bread and butter is gaming and since they now have more competition actually focusing on that is obvious at this point.
The dedicated Videos link on Steam has already been removed.