I've been following DU obsessively since it was first announced, and know from experience that MMOs at launch are rough at best. Even more with a beta launch...
Still, it's a little vexing that this game was built on the promise that everyone can play together in a shared world -- that's a huge part of the marketing. When the servers crumble almost right away and remain unreliable through the weekend, I'm not sure if they really took this promise seriously. Most big launches have struggles in the first day or so, but I had different connection problems on my extremely fast internet through the whole weekend.
If they can't scale at launch, how are they going to scale when players have created huge organizations and battles?
If they had marketed this as a public alpha, I think people would be more forgiving. I don't really think this is a beta version -- and frankly I believe they have years to go before the product is refined enough to launch or even call a beta.
I have strong No Man's Sky vibes where marketing materials capture a concept that the game itself doesn't replicate.
I will definitely come back and check out the progress, but I don't expect it to be really playable for another year or two. In my cynical mind, I can't help but wonder if the motivation to go to a subscription model was because they knew it wouldn't be ready for a while and need a more steady source of funding to keep afloat.
PS: to top it off, I just got the email about resetting everyone's passwords...I know first-hand how hard tech is, but I have strong doubts that a company can delivery an extremely ambitious cutting-edge multiplayer experience when they can't even handle passwords securely...