The evidence is the fact that it's says so on the application form. Going by your argumentation, even if they said "no, it's working like it should, active account required", you would still not believe them.
The judgement on whether delete, lock or merge topics lies by the moderator. If people on the english forums would finally get it into their heads that opening 10 different threads on the same topics with different formulations doesn't do anything except inciting spam of repeated posting in all those 10 threads, we'd see less deletions sending wrong signals. Other language forums don't seem to be having this problem, why does this one do?But deleting the thread that includes the complaint gives me all kinds of bad singnals. I would also mention that by taking it upon yourself to take a confrontational stance with those that are dissatisfied in the presence of a potentially serious PR blunder, you do SE no favors.
That's why a moderator has the "lock" button, which is what has been used in previous, equivalent cases. Mind you, that thread was no duplicate, as it asked about a very specific issue, that wasn't included in the others, that are generic complaints about not being invited.
Again, the "climbing mirrors" metaphor comes to mind.
The alpha starts on the 28th, I think the servers are still down.