It's A Simple Question: When Exactly Can NON utube Videos Be Uploaded, If Ever.

From what I understand of it, it's as Arbitrageur says, the code on ATS converts the video ID we put on that "Please enter the YouTube video number." box and converts it into the code for embedding YouTube videos.

Different forums use different methods, but, as far as I know, they all use a similar system, as embedding videos needs the user to post some kind of HTML and/or Javascript code, and any of those could include malicious code to either affect the site or (more likely) the users visiting the page.

In this particular case, this is the code to embed that CNBC video:


As you can see, it's bit of HTML code with an IFrame (Inline Frame), that basically creates a page with different content inside the page where the code is embedded.
If the forum code allowed people to post a direct embed code, they would need to, at least, allow people to post an IFrame, basically allowing people to post content from whatever source they would want, with all the risks something like that brings.

So, what happens is that, usually, allowing embedding of videos (or other content) from other pages needs to be done on a case by case system, with specific code for each site, so we would need code for YouTube, CNBC, Vimeo, Dailymotion, whatever.

Some forum software packages have the possibility of adding some kind of add-on to add features to the forum, but on an custom-made forum like ATS that has to be done manually.

PS: in the specific case of this video, you can use the YouTube version of the "Munich Security Conference: Finding a way out of the pandemic" video, posted to YouTube by CNBC, and use this code to jump to the same point the CNBC video you talk about in the opening post starts: U70Q9WqbMFM?t=407

Resulting in this:


Edited to add that, for some reason, YouTube is jumping whatever time it wants to every-time I reload the page...