A generated visa BIN is just fake credit card numbers with fake cvv and fake expiration date, why a fake credit card works on Netflix? well simple, since Netflix does not charge money on the first month.
But you need some money in the cc account to verify that the card is not fake, how does your method get around this ?
This is not true. I recently applied a prepaid credit card that had a zero balance on it in order to create an account. Netflix approved my account, even though there was no balance on the card. I believe that if Netflix isn't charging a card, all they are looking for are valid credit card numbers in order to approve the free trial.
I will also say that even after the trial, the account was still valid for another month while they attempted to repeatedly charge my zeroed card for payment. So, in theory, I got 4 months for free with a zeroed card.
They must have changed it, I have tried prepaid cards before with no balance and they have always rejected them saying not enough balance on the card and the ones I have used, even recently show that Netflix have removed a small amount and then deposited it back again.