If your model of the future of the BBC is that the license fee, which costs about as much as Netflix, should give you a comparable product - then if Netflix have 10x the budget, the BBC's going to have a tough time competing.
They should also sell subscriptions to those outside the UK as well, there is enough demand for sure.
Some of this value proposition question will depend on what the BBC is going to do on their pricing. We can be certain what Netflix is going to do.