Two of the biggest RPG content creators out there - the Matts Coleville and Mercer - are actively making their own games right now and talking about their design choices. Ditto with Dungeon Coach. DM's Lair switched to
PF2 a while back as did Rules Lawyer.
@SlyFlourish talks about Shadowdark all the time. Bob World Builder recently had a
video specifically featuring non-D&D games.
Seth Skorkowsky mostly talks about CoC and Traveler.
The Alexandrian talks about tons of different systems. These are examples I can come up with off the top of my head. So I think you sample size of one video from one creator is not necessarily representative of "YouTube influencers be like..." (sorry, I may have watched too many YouTube influencers!)