TLS DNS and DNSCurve perform essentially the same function, so it doesn't make much sense to compare one with DNSSEC and one without. What blurs the line a little is that DNSCurve is explicit about its goal of providing bottom-up DNS security --- in a world with near-universal DNSCurve deployment, the need for DNSSEC would be minimized. But that's in fact true of TLS DNS, as well --- it's just not something the IETF is explicit about.

Both DNSSEC and DNSCurve are basically dead-letter standards at this point; interestingly, the stake through both their hearts is DNS over TLS or HTTPS, but for different reasons: DNSCurve, because DoTLS essentially replaces the entire protocol, and DNSSEC because DoTLS reveals (through its rapid adoption, among other things) how marginal DNSSEC's contribution actually is.