For example, as much as I'd like to praise Go's stdlib because of how far it can take you, the defaults for its HTTP server are "the URL+headers of a request can take as much as 1MB" and "no timeouts at all, wait forever if necessary". See the `Server` type and the `ListenAndServe` function (not method) from the `net/http` package for more details.
They're probably trying to be as conservative as possible, but 1MB is huge.