Why is this there?
It’s like an ad on a website, a very obnoxious one.
Please add a tab/button somewhere to hold this content. It does not belong on the game launcher window. It is not news about your game. Even your own videos are just thumbnails until we click them
Nobody ever, should be forced into watching a video.
Get rid of this shyte!
Are you happy that you got that off of your chest? What will you complain about tomorrow? 
Where are you seeing a video add autoplay? I went through each and every game tab on my launcher and am not seeing any auto play videos. Diablo has 3 News articles, are all links to web pages with text print blogs, not videos.
There are some videos for other games, but all have a play button arrow on them. None are auto playing.
Are you sure something else is not causing you issues?
i haven’t opened up Bnet today, but there are often times when certain games (SC2? OW?) have auto-playing live video for me related to competitions or whatever. That is one reason I always close down Bnet after I launch a game.
There’s only one thing on my Diablo 3 tab on the launcher and it’s a still picture saying the new patch is live.
However I do wish there was a thing saying Season 18 is about to start, that would be cool.
Yeah, I don’t see any video on my Bnet launcher either - just a screen telling me about the start of Season 18.
On the news window if you hover over it with the mouse you will see faint arrow keys on the edges. It lets you switch between news articles that are currently featured. The Season start one is in there.
I found one autoplay, but it appeared to be a fluid GIF type with no sound. Still resource intensive given how poorly the Battle.net app is optimized (it really is a hot mess), but thankfully none of the videos autoplay for me in either the live or Beta branches.
From time to time, an Overwatch League button appears at the top of the Battle.net launcher which, if clicked on, will result in an auto-playing video stream…
http://ximg.co.uk/images/2019/08/24/d3_battlenet_overwatch_league.jpg
Overwatch has it for me, it just auto plays a twitch stream popular in my geographical region, and the updates are all in my first language and can’t be changed to english.