The media side is the sell side the VC side is the buy side. You trumpet your companies and people so you have more brand around them. Other people buy into those companies and brands which increases the value of those items. Rinse and repeat until you go to the public markets or found an exit worthwhile.

They realized that buy having strong promotion that increases the perceived value of their people, companies and founders. It also makes getting LPs easier.

Look to Elon for a core example of this phenom.

Arguing if they are a media company or a VC is irrelevant - it serves the same purpose.