However, this kind of advertisement will attract more players to deposit to their webaite if they see they are able to win huge like that of stremear.
This happens but not to all people. Smart gamblers will always think about what will actually happen or might happen if they deposited and play on the website, people who know how really gambling works will not go in and deposit right away just because they saw someone winning chunks of money on the said site.
This is correct as I also refer above where it's up to the viewers point. Depositing money is still involved here so there will be a hesitation at first.
And to win, the gamblers themselves need to play, playing with RNG, and it doesn't mean that if the streamer is lucky, the same result will happen to others.
Worse thing to think of, not because you watch someone who won a huge amount of money means that if you try it out by yourself, you'll also get the same result. Think again and assess yourself, unless you are an avid fan who blindly follows whatever your idol is doing.
streamers got the influenced no question about it, but wise gamblers/followers value their money and they'll do their very best to avoid losing / spending a lot.