It isn't your subscription that funds Netflix's original content, it's investor cash burn. To the tune of about ~$14B since 2011.

They won't keep paying that bill forever.

Think about that for a second. All of those Netflix subscriptions and it's still a flaming fourteen billion dollar crater.

How are they going to close the gap? Where are the new subscribers? How much will the rate go up?

The answer is neither of those. It's far more likely that the money faucet going to content will change first.