From
DCL's perspective, they are doing that with the onboard restrictions rather than embarkation restrictions.
Imagine the headlines -- "Disney says 'No kids allowed!" That would be horrendous PR for the company, probably worse than staying closed. So instead they ramped up the restrictions onboard. I do think their current protocols lean towards pushing families into a decision to cancel (or not book), without outright denying them access.
From what I've seen, DCL is not necessarily making this demographic happy. Families of young kids aren't directly precluded from cruising, but DCL isn't making it easy either.
Maybe I missed something, but I don't see mention of adding more family friendly activities. A lot of things are not available or limited -- things that are generally important to these families: no nursery, no character meet & greets, no deck parties, no sports deck, virtual queue for the family pools, reservations required at the Club/Lab, limited time allowed at the Club/Lab. These are all things that usually help make DCL family friendly and they are currently missing with no promise of alternate activities. Many families are not happy and cancelling their planned cruises (or intend to cancel if things don't change).