I don't think we've had full stadiums, but we've definitely had more than 3000 people in a stadium. At a glance it seems like that'll be cut to just 500 now in total, although I think something like 500 per stand should be possible in the bigger stadiums (by Danish standards) seeing as it's basically separate gatherings so to speak.
I agree, but that's why they're trying to keep things open but putting in place stricter regulations. We were doing pretty well for a decent amount of time without numbers rising, but it seems like people have started being too lax in terms of keeping their distance, washing hands etc. after the summer holidays ended. I think the new restrictions are based on what they think have been drivers of new infections.
I think it's possible to keep most things open with certain regulations put in place without numbers rising uncontrollably. However (and this is the big one), it requires people to actually take things seriously and not just start acting the prick. So people should be able to work, go to school and go out for dinner etc. in a sensible way if they instead skip the parties and what not that aren't really that important in the grand scheme of things.
We also have an app that's supposed to track whether you've been in contact with someone (and have had it for some time), yet I don't think very many people have actually installed it. There's been very little in terms of people talking about it and promoting it etc.