Some articles have something like:

<meta property="article:publish_time" content="data"/>

Spotify has:

<meta name="music:release_date" content="data"/>

YouTube has:

<meta itemprop="datePublished" content="data"/>

There seems to be at least "some" attempts to clear this, but it's outdated:

https://github.com/kevinSuttle/html-meta-tags

Why no organization manages it, or maybe there is, but I have not heard about it?

Is meta is a nice bag for all 'custom' stuff? We can put there whatever we want?