[tptacek]

It's a little weird to refer to this as "false", since Pornin's RFC was published after EdDSA. Bernstein isn't writing an elaborate blog post about Bitcoin; he references Bitcoin as a way to provide context for readers who might not be familiar with actual protocols that use ECDSA.

The overwhelming majority of ECDSA applications do not use deterministic DSA; deterministic DSA is a novelty.

[vbuterin]

EdDSA uses something very similar to RFV6979, so the author had to have realized that just retroactively adding that small piece to ECDSA was a possibility. So I don't think it's really fair to call determinism an intrinsic property of either algorithm.