Confirmation Bias: “All the streams I see are streamers, and I never see anything from the people who aren’t streamers because they don’t stream, therefore all the people in the beta are streamers, because that’s the only people I see”.
There must be more than streamers in the beta, because otherwise the streamers won’t have enough unique content for their channels. Streamers want a bunch of non-streamers so they have a way to generate content that won’t appear on 4 other streamer’s sites.
The streamers are a small segment, that Blizzard definitely invites specifically so you can see the Beta and hype up the game. It also allows more eyeballs on the product to ensure that more bugs are seen and identified.
Streamers are not a bad thing, and before we had streamers, there were plenty of exactly the same threads saying “Why didn’t I get a beta invite?”
It’s just FOMO. Fear of Missing Out.
You won’t, and none of the progress on the Beta is retained. All knowledge is immediately shared amongst all the sites and everyone has the ‘best methods’ down pat. Just wait for the pre-patch then release, and we can all dive in at the same time.