[Feature Request] Allow vanilla clients to join a server with CarryOn #1004

Is your feature request related to a problem? Please describe.
When I install CarryOn on a server all clients need to install it to join. As CarryOn is a pretty light mod that I sometimes want on servers where not everyone wants to use mods, however this is not possible as vanilla clients cannot join a server with CarryOn.

Describe the solution you'd like
I would like it if it were possible to allow vanilla clients to join a server with CarryOn. Vanilla clients would not be able to pick up things using CarryOn, while clients with the mod could. This way people can choose whether or not they want to install the mod and those who do can use it.

Describe alternatives you've considered
I've looked at server-side alternatives but none are on neoforge (the platform I use) and none are as good as CarryOn.

Additional context
This error occurs when a vanilla client joins a server with CarryOn: