Rednet has existed for a long time now, seen as another, "easier" way to use the modem API. rednet has a good concept in mind, but it's time has gone now, as it's insecure and new players confuse the modem API with rednet and whatnot. Rednet's only really a wrapper, and why not deprecate it. There are much better alternatives like SMT (secure modem transit!) that do what rednet and modem do, but in more secure ways.

Discussed this in Discord, but just writing up my thoughts so there's a bit more of a traceable record:

Rednet is meant to be a simple, easy-to-use wrapper over the modem API. It's never pretended to be secure, nor will it ever handle every use-case. It's just nice and easy to use when either getting started, or when you don't need to worry about messages being encrypted/authenticated.

Yea, I kinda understand it now. I didn't really think that CC was like a mod for relatively small servers or singleplayer back in the day. And I guess the people on big servers yell at you anyway so there's no need to deprecate it then.