From the clip attached, “les réseaux sociaux” is in common use in France. 

Wordreference also gives only “les réseaux sociaux” as translation.

As médias sociaux is also found on the net, this may indicate that it has limited use in France, or differences in use across francophone countries (one list of ‘official terms’ I found that included this was from Quebec).

https://www.wordreference.com/enfr/social%20media

The direct translation to English of "les réseaux sociaux" is "social networks". Maybe that clears it up!

The French think of it as a network (réseau), not so much as media.

I can confirm that "les médias sociaux" is used more commonly in Quebec/French speaking Canada. Radio & TV both use it, likely because of American English influence.