Because it's not about DNSSEC in itself ... If DNSSEC automation makes DNSSEC more accessible and widely deployable, but a substantial part of domains cannot deploy it, then DNSSEC adoption will not improve to substantial numbers.
One such system is Domain Name System Security Extensions (DNSSEC). Because of the larger signature and key sizes associated with PQC algorithms, it might be the case that DNSSEC-related queries more often require the use of TCP instead of UDP.