Should audio and video tags be allowed?

Sorry to revive this old topic; I couldn’t find any answers to my question in newer topics.

Re: using Oneboxing as a solution, my goal is to be able to self-host some private video content (mp4). (One of the goals is to be able to use Discourse’s authorization/group-based access controls).

I think something as simple as this would normally work for me:

<video width="320" height="240" controls>
  <source src=""/uploads/default/172/4158c00ffee987c5.mp4"" type="video/mp4">
</video>

I understand how to use the Onebox feature for hosting via YouTube etc, but how can I replicate similar functionality for self-hosted video?

Thanks much!
Matt