DNS Flag Day 2020: DNS servers must support both UDP and TCP queries Industry group wants to make DNS over TCP support mandatory May 22, 2019 https://www.zdnet.com/article/dns-flag-day-2020-dns-servers-must-support-both-udp-and-tcp-queries/
Great news, makes handling DNSSEC more sane when riding it with TCP than size limited UDP. And if the root DNS servers start to support DNS-over-TLS and/or DNS-over-HTTPS, just like they now all support DNSSEC, then snoops have hard time of spoofing, MitM and inspecting DNS data