> I think its pretty unlikely (in terms of db design) that you'd have a consistent system that could service reads but not writes during some manner of outage.

Consider a bank account. I can consistently service writes that add or subtract from the balance as long as I can guarantee durability and is willing to blindly update without a consistent view of the balance.

I can only service consistent reads when I can guarantee that I have seen every committed transaction.

In this case we opt for availability over consistency when presenting the current balance, but for consistency when e.g. cutting statements (through the brute-force method of just waiting until all settlement for the relevant dates has occurred).