I did not know that people are actually streaming the PvP from FFXIV. Do they have an audience? I cant imagine that to be more than 20.
From what i have, sadly, experienced is that once nice people became.... not so nice anymore after achieving, or rather, grinding, certain Ranks. People i knew from the earlierst seasons cant be bothered to say hi anymore or anything really.
People often Claim that the Community in FFXIV is so nice and all, the reality is that they just dont express their "true Feelings" openly in Game since SE is quick to punish. Dont you dare being on one of the bigger Discords.... there, they show their True colors

I guess the same is correct for Streamers. They expose themselves in a way by streaming and try to fortify their position by acting like a Rank 1 WoW Gladiator Championship Winner.
That said, no. I do not think Streaming is helping in any way. Just as all those seemingly nice and Helpful discords that try to get you in so their owners can tell everyone what a big community they have. Many people claim to be wanting to help new players, in truth they just want more people they can bash behind their backs. Now i know that all sounds very Fatalistic and negative, BUT there are actual nice people. Usually those who keep more to themselves, those who do not boast about their Ranks and achievements, those are the nice ones.