I would hope that priority is given to cruisers truly traveling solo.
Absolutely. I'd hate to see the bookings eaten up by those who could share a cabin but see this as a way to kill two birds with one stone, with more space and private bedrooms at night if they get connecting cabins. But I fear that is what will happen.
They are also going to allow these cabins to be blocked out for group space, and they can be booked for a couple although that will incur the usual double occupancy fees.