No they aren't more reputable, they're cheaper and unfortunately have greater impact. A streamer playing a game to their 10k audience, despite the game being shit, will still result in guaranteed sales in a way that makes full blown marketing campaigns in traditional media pale in comparison.
It literally doesn't matter how good or bad they are at acting, all that matters is the game gets coverage on their channel, that's exactly what the campaigns are paying them thousands for. Yes, thousands.