In most servers. there's a limit for the request-URI that limits the request size like: apache, nginx, python http.server. it's required to keep the server smooth and inform the user when his requests exceeds the max limit of characters and the server won't process the request it will just return an error message. processing such a requests specially when it interacts with the server increases the CPU/memory usage resulting in DDoS attacks.

The limit should be for the first request line that includes the path the user is visiting and the request method. if you gonna make any changes.