At least Fallout 76 is actually doing beta correctly. They are encouraging people to break the game so they know what they need to fix and make the game playable on launch...which is astounding to hear from Bethesda. In general though, most companies do beta as "demo version of game called beta."
God that was an absolute mess. My friends and I were furious. Like luckily I have pretty solid internet so I was able to redownload it but I was the only one out of my friends that got to play the first day. I guess on the bright side they increased the beta length for today. It's a pretty big "bug" when your launcher deletes the entire game for you. :^)