Yes, this is exactly what's going on if we talk about established and honest gambling sites: some people lose much more than they expect, much more than the highest house edge imaginable, to slots, or whatever they play there, because of bad luck. And then some of them think that the site is scamming them and streamers that promote that site are scammers.
sometimes this looks strange, viewers imitate what streamers do, which is clear that it's gambling, but in other days, they try it because they are seeing the wins amount from streamer. They don't think about the risks before they start, then accuse as scam in comments. I've also watched live gambling streaming, when the streamer won. Even though it's not their money though, I feel normal.
Maybe when I watched it, the streamer was lucky. Of course, I didn't follow the streamer's directions to play at the place he was promoting, because for me, the place where I played was the most appropriate choice, because I would definitely be paid if I won. Watching them, just to know the game.
That's right, he was lucky. And it can happen to anyone of us, so, I see no lie or attempt to scam there.
Copying streamers moves is pointless, you are doing the right thing with not following them. As for the particular site they playing on, honestly, I don't think it can be a scam site. Gambling sites pay a lot of money to those streamers, and scam sites are not capable of that.