Dns is so broken in many different ways. It’s crazy it’s still the back bone of the internet when it’s insecure awful nonsense. It’s just ingrained.
Second, if the response has to be larger than the request, send the requestor an address-specific value in a small initial response, e.g. HMAC of a secret and the sender IP. Then any request that incurs a large response has to contain that value. If the sender is spoofing the IP address and can't receive the small response sent to that address, they can't cause a large response to be sent there.
This can't be done with DNS because of "security" middleboxes. They ossify the protocol because they reject anything they don't understand, and they don't understand new versions of the protocol even if both of the endpoints do. So the protocol gets frozen in time and no security improvements can be made because of the things that claim to be there to improve security.
There is little actual reason for security middleware to not keep up.
Apart from human readability, how so?
This stuff is built on the foundation of puffing out EnTeRpRiSe ScAlE egos with "look at all this vast complexity that I made, I am a god". It's not built on a technical foundation of always moving the needle forward just because you can and because it's cool and the right thing to do.
Sooo, all the $$$ get spent on dashboards and analytics screens and front panel designs and logos and stuff. The actual DNS bits? Probably /r/programminghorror material.
The internet is IP. It is very robust. DNS is an application over the top of the Internet.
I don't think very many other applications will work without DNS either, although I never did much competitive testing.