It means something because it shows that users aren’t being put off signing up by the delayed launch of current accounts, the number of users signing up each day is growing steadily.
I agree that this is the much more meaningful metric. The last time Monzo mentioned it in their crowdfunding deck in January, 60% of users who’d signed up were still active (using their cards once per week). As far as I know, we haven’t had an update since then.
So those are the facts, perhaps my comment sounded like a PR response because I’m not making assumptions like that 
despite not knowing whether the wait will be a major problem for lots of Monzo users & therefore, whether it will be a significant issue for Monzo or not?
My point is that you can only speak for yourself, on whether the wait is going to put you off Monzo completely. And if you are concerned for yourself, then fair enough 
Edit - It’s also worth mentioning that it’s already in Monzo’s interest to be working as hard as they can to get the current accounts ready & from what I’ve heard, they are.