The part that's missing in DNS is the ability to tell people that the cache expired. You can't really do this in DNS itself since a cached response will never hit the network. You could add a signal in the application protocol for example: <meta name="dns-refresh" value="[.. some date ..]">.

You'd also have to do that for SMTP, IMAP, etc. Probably not worth the complexity as low TTLs seem to work well enough with few enough downsides. DNS is already a tricky enough protocol.